Tax Credit Investments Tax Credit Investments - Affordable Housing Tax Credit Investments, Other Tax Credit Investments, and Related Unfunded Commitments (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Other Assets
Other Assets [Abstract]
Affordable housing tax credit investments, net	$ 31,370	$ 32,094
Other tax credit investments, net	64,141	70,681
Total tax credit investments, net	95,511	102,775
Other Liabilities
Other Liabilities [Abstract]
Unfunded affordable housing tax credit commitments	7,330	7,330
Unfunded other tax credit commitments	6,165	12,545
Total unfunded tax credit commitments	$ 13,495	$ 19,875