Significant Unobservable Inputs used in Fair Value Measurement (Detail) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Interest rate lock commitments
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value		$ 10,133	$ 2,526	$ 1,920	$ 4,397
Valuation Technique		Discounted Cash Flow
Weighted Average Closing Ratio		75.74%
Mortgage servicing rights
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair value		$ 188,331	$ 243,389	$ 250,963	$ 227,297
Valuation Technique		Discounted Cash Flow
Weighted Average Constant Prepayment Rate	[1]	11.54%
Weighted Average Discount Rate		10.02%

[1] Represents annualized loan repayment rate assumptions.