Annual report pursuant to Section 13 and 15(d)

Revenue from Contracts with Customers (Disaggregation of Revenue) (Details)

v3.20.1
Revenue from Contracts with Customers (Disaggregation of Revenue) (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2019
Sep. 30, 2019
Jun. 30, 2019
Mar. 31, 2019
Dec. 31, 2018
Sep. 30, 2018
Jun. 30, 2018
Mar. 31, 2018
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Disaggregation of Revenue [Line Items]                      
Advisory fees $ 395,735 $ 374,532 $ 363,580 $ 335,455 $ 355,121 $ 348,875 $ 357,756 $ 329,384 $ 1,469,302 $ 1,391,136 $ 1,268,152
Corporate                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 3,242 4,872 3,960
Independent Advisory and Brokerage Services | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 1,204,326 1,161,043 1,140,380
Ladenburg | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 75,523 78,094 66,680
Insurance Brokerage | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 186,211 147,127  
Commissions                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 724,605 696,331 536,028
Commissions | Corporate                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 0 0  
Commissions | Independent Advisory and Brokerage Services | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 531,503 540,523  
Commissions | Ladenburg | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 9,407 11,468  
Commissions | Insurance Brokerage | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 183,695 144,340  
Advisory fees                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 510,609 474,423 560,930
Advisory fees | Corporate                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 0 209  
Advisory fees | Independent Advisory and Brokerage Services | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 502,699 467,044  
Advisory fees | Ladenburg | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 7,910 7,170  
Advisory fees | Insurance Brokerage | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 0 0  
Investment banking                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 54,043 56,256 46,453
Investment banking | Corporate                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 0 (854)  
Investment banking | Independent Advisory and Brokerage Services | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 961 947  
Investment banking | Ladenburg | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 53,082 56,163  
Investment banking | Insurance Brokerage | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 0 0  
Principal transactions                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 1,452 (328) 857
Principal transactions | Corporate                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 169 174  
Principal transactions | Independent Advisory and Brokerage Services | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 26 22  
Principal transactions | Ladenburg | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 1,257 (524)  
Principal transactions | Insurance Brokerage | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 0 0  
Interest and dividends                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 5,289 4,971 2,550
Interest and dividends | Corporate                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 1,715 1,566  
Interest and dividends | Independent Advisory and Brokerage Services | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 2,551 2,566  
Interest and dividends | Ladenburg | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 1,023 839  
Interest and dividends | Insurance Brokerage | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 0 0  
Service fees                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 132,029 119,430 85,330
Service fees | Corporate                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 1,155 888  
Service fees | Independent Advisory and Brokerage Services | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 128,546 116,047  
Service fees | Ladenburg | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 2,328 2,495  
Service fees | Insurance Brokerage | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 0 0  
Other income                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 41,275 40,053 $ 36,004
Other income | Corporate                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 203 2,889  
Other income | Independent Advisory and Brokerage Services | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 38,040 33,894  
Other income | Ladenburg | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 516 483  
Other income | Insurance Brokerage | Operating Segments                      
Disaggregation of Revenue [Line Items]                      
Advisory fees                 $ 2,516 $ 2,787