Business Combination - Assets Acquired and Liabilities & Equity Assumed (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Jun. 01, 2017	Dec. 31, 2016
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Goodwill	$ 170,153		$ 6,788
RidgeWorth
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Cash and cash equivalents		$ 39,343
Investments		5,516
Accounts receivable		19,941
Furniture, equipment and leasehold improvements		5,505
Intangible assets		275,700
Goodwill		163,365
Deferred taxes, net		6,590
Other assets		3,003
Total Assets		1,480,875
Liabilities
Accrued compensation and benefits		18,263
Accounts payable and accrued liabilities		11,938
Other liabilities		2,601
Noncontrolling Interests of CIP		15,731
Total Liabilities & Noncontrolling Interests		933,793
Total Net Assets Acquired		547,082
Consolidated investment products | RidgeWorth
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets [Abstract]
Cash and cash equivalents		38,261
Investments		902,493
Other assets		21,158
Liabilities
Notes payable of CIP		770,160
Securities purchased payable and other liabilities of CIP		$ 115,100