Significant Unobservable Inputs used in Fair Value Measurement (Detail) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Interest rate lock commitments
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value		$ 2,526	$ 4,397	$ 258
Valuation Technique		Discounted Cash Flow
Weighted Average Closing Ratio		75.01%
Mortgage servicing rights
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value		$ 243,389	$ 227,297	$ 241,018
Valuation Technique		Discounted Cash Flow
Weighted Average Constant Prepayment Rate	[1]	7.35%
Weighted Average Discount Rate		10.01%

[1] Represents annualized loan repayment rate assumptions.