Goodwill and Other Intangible Assets - Summary of Goodwill Activity (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Roll Forward]
Goodwill, gross, beginning balance	$ 188,541	$ 188,541
Additions	360,859	0
Foreign currency translation adjustment	(441)	0
Goodwill, gross, ending balance	548,959	188,541
Wealth Management [Member]
Goodwill [Roll Forward]
Goodwill, gross, beginning balance	0	0
Additions	356,386	0
Foreign currency translation adjustment	0	0
Goodwill, gross, ending balance	356,386	0
Tax Preparation [Member]
Goodwill [Roll Forward]
Goodwill, gross, beginning balance	188,541	188,541
Additions	4,473	0
Foreign currency translation adjustment	(441)	0
Goodwill, gross, ending balance	$ 192,573	$ 188,541