Other Noninterest Income and Other Noninterest Expense - Summary of Other Noninterest Income (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015		Sep. 30, 2014
Other Income and Expenses [Abstract]
Fund management fees	$ 4,074	$ 3,574	$ 11,657		$ 9,888
Service-based fee income	1,931	2,180	6,450		6,459
Gains (losses) on revaluation of foreign currency instruments	186	(12,640)	(11,667)		(12,347)
Other	4,886	1,525	15,875		10,601
Total other noninterest income	$ 11,077	$ (5,361)	$ 22,315	[1]	$ 14,601

[1] Amounts for the nine months ended September 30, 2015, have been revised to reflect the retrospective application of new accounting guidance adopted in the second quarter of 2015 related to our consolidated variable interest entities (ASU 2015-02). Amounts prior to January 1, 2015 have not been revised for the adoption of this guidance. See Note 1— "Basis of Presentation” of the “Notes to Interim Consolidated Financial Statements (unaudited)” under Part I, Item 1 of this report for additional details.