Goodwill and Other Intangible Assets - Other Intangible Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	$ 138,593	$ 143,020
Accumulated Amortization	(92,209)	(93,849)
Valuation Allowance	(900)	(289)
Net Intangible Assets	45,484	48,882
Loan servicing rights
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	73,002	75,932
Accumulated Amortization	(52,634)	(59,251)
Valuation Allowance	(900)	(289)
Net Intangible Assets	19,468	16,392
Core deposits
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	61,504	62,714
Accumulated Amortization	(37,562)	(31,934)
Valuation Allowance	0	0
Net Intangible Assets	23,942	30,780
Other
Finite-Lived Intangible Assets [Line Items]
Gross Intangible Assets	4,087	4,374
Accumulated Amortization	(2,013)	(2,664)
Valuation Allowance	0	0
Net Intangible Assets	$ 2,074	$ 1,710