Quarterly report pursuant to Section 13 or 15(d)

Fair Value of Assets and Liabilities (Schedule of Fair Value of Assets and Liabilities Measured on a Nonrecurring Basis) (Details)

v3.8.0.1
Fair Value of Assets and Liabilities (Schedule of Fair Value of Assets and Liabilities Measured on a Nonrecurring Basis) (Details) - USD ($)
$ in Thousands
Sep. 30, 2017
Dec. 31, 2016
Liabilities    
Contingent consideration payable $ 2,775 $ 7,144
Carrying Value | Fair Value, Measurements, Nonrecurring    
Assets    
Cash and cash equivalents 100,739 98,930
Notes receivable, net 33,984 32,611
Other receivables, net 48,791 54,634
Total assets 242,163 228,520
Liabilities    
Accrued compensation 28,607 26,299
Commissions and fees payable 62,384 60,594
Accounts payable and accrued liabilities 40,120 32,732
Accrued interest 482 281
Notes payable, net 28,182 26,417
Total liabilities 159,775 146,323
Fair Value | Level 2    
Liabilities    
Notes payable, net 26,425 24,494
Fair Value | Fair Value, Measurements, Nonrecurring    
Assets    
Cash and cash equivalents 100,739 98,930
Notes receivable, net 33,984 32,611
Other receivables, net 48,791 54,634
Total assets 242,163 228,520
Liabilities    
Accrued compensation 28,607 26,299
Commissions and fees payable 62,384 60,594
Accounts payable and accrued liabilities 40,120 32,732
Accrued interest 482 281
Notes payable, net 26,425 24,494
Total liabilities 158,018 144,400
Fair Value | Fair Value, Measurements, Nonrecurring | Level 1    
Assets    
Cash and cash equivalents 100,739 98,930
Notes receivable, net 0 0
Other receivables, net 0 0
Total assets 100,739 98,930
Liabilities    
Accrued compensation 0 0
Commissions and fees payable 0 0
Accounts payable and accrued liabilities 0 0
Accrued interest 0 0
Notes payable, net 0 0
Total liabilities 0 0
Fair Value | Fair Value, Measurements, Nonrecurring | Level 2    
Assets    
Cash and cash equivalents 0 0
Notes receivable, net 33,984 32,611
Other receivables, net 48,791 54,634
Total assets 141,424 129,590
Liabilities    
Accrued compensation 28,607 26,299
Commissions and fees payable 62,384 60,594
Accounts payable and accrued liabilities 40,120 32,732
Accrued interest 482 281
Notes payable, net 26,425 24,494
Total liabilities 158,018 144,400
Receivables from clearing brokers | Carrying Value | Fair Value, Measurements, Nonrecurring    
Assets    
Receivables 56,722 41,492
Receivables from clearing brokers | Fair Value | Fair Value, Measurements, Nonrecurring    
Assets    
Receivables 56,722 41,492
Receivables from clearing brokers | Fair Value | Fair Value, Measurements, Nonrecurring | Level 1    
Assets    
Receivables 0 0
Receivables from clearing brokers | Fair Value | Fair Value, Measurements, Nonrecurring | Level 2    
Assets    
Receivables 56,722 41,492
Receivables from other broker-dealers | Carrying Value | Fair Value, Measurements, Nonrecurring    
Assets    
Receivables 1,927 853
Receivables from other broker-dealers | Fair Value | Fair Value, Measurements, Nonrecurring    
Assets    
Receivables 1,927 853
Receivables from other broker-dealers | Fair Value | Fair Value, Measurements, Nonrecurring | Level 1    
Assets    
Receivables 0 0
Receivables from other broker-dealers | Fair Value | Fair Value, Measurements, Nonrecurring | Level 2    
Assets    
Receivables $ 1,927 $ 853