Goodwill and Other Intangible Assets - Other Intangible Assets (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	$ 132,384	$ 143,020
Accumulated Amortization	(86,795)	(93,849)
Valuation Allowance	(746)	(289)
Net Intangible Assets	44,843	48,882
Loan Servicing Rights
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	66,793	75,932
Accumulated Amortization	(50,079)	(59,251)
Valuation Allowance	(746)	(289)
Net Intangible Assets	15,968	16,392
Core Deposits
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	61,504	62,714
Accumulated Amortization	(34,851)	(31,934)
Valuation Allowance	0	0
Net Intangible Assets	26,653	30,780
Other
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	4,087	4,374
Accumulated Amortization	(1,865)	(2,664)
Valuation Allowance	0	0
Net Intangible Assets	$ 2,222	$ 1,710