Quarterly report pursuant to Section 13 or 15(d)

Intangible Assets - Intangible Assets Subject To Amortization (Details)

Intangible Assets - Intangible Assets Subject To Amortization (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Indefinite-lived Intangible Assets [Line Items]
Weighted-Average Estimated Useful Life (years)	9 years 6 months 33 days
Gross Carrying Amount	$ 205,783	$ 202,713
Accumulated Amortization	$ 80,283	64,782
Technology
Indefinite-lived Intangible Assets [Line Items]
Weighted-Average Estimated Useful Life (years)	7 years 10 months 24 days
Gross Carrying Amount	$ 25,563	25,563
Accumulated Amortization	$ 14,938	12,488
Relationships with financial advisors
Indefinite-lived Intangible Assets [Line Items]
Weighted-Average Estimated Useful Life (years)	15 years 3 months 18 days
Gross Carrying Amount	$ 113,681	110,671
Accumulated Amortization	$ 38,350	32,028
Covenants not-to-compete
Indefinite-lived Intangible Assets [Line Items]
Weighted-Average Estimated Useful Life (years)	3 years 10 months 24 days
Gross Carrying Amount	$ 6,095	6,035
Accumulated Amortization	$ 4,308	3,347
Customer accounts
Indefinite-lived Intangible Assets [Line Items]
Weighted-Average Estimated Useful Life (years)	8 years 3 months 18 days
Gross Carrying Amount	$ 2,029	2,029
Accumulated Amortization	$ 1,944	1,765
Trade name
Indefinite-lived Intangible Assets [Line Items]
Weighted-Average Estimated Useful Life (years)	7 years 8 months 12 days
Gross Carrying Amount	$ 16,910	16,910
Accumulated Amortization	$ 9,461	7,790
Renewal revenue
Indefinite-lived Intangible Assets [Line Items]
Weighted-Average Estimated Useful Life (years)	7 years 10 months 24 days
Gross Carrying Amount	$ 41,381	41,381
Accumulated Amortization	$ 11,168	7,263
Referral agreement
Indefinite-lived Intangible Assets [Line Items]
Weighted-Average Estimated Useful Life (years)	6 years 7 months 6 days
Gross Carrying Amount	$ 124	124
Accumulated Amortization	$ 114	$ 101