Fair Value - Fair Value Measurement (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2017 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assumed Gain/(Loss) From Loan Sale	$ (3,850)
Interest Rate Movement Effect	1,362
Servicing Rights Value	8,000
Security Price Change	(3,343)
Total Fair Value Measurement Gain/(Loss)	2,169
Mortgage Banking [Member] | Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | Rate Lock Commitments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notional or Principal Amount	603,327
Assumed Gain/(Loss) From Loan Sale	(2,871)
Interest Rate Movement Effect	1,771
Servicing Rights Value	5,620
Total Fair Value Measurement Gain/(Loss)	4,520
Mortgage Banking [Member] | Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | Forward Sales Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notional or Principal Amount	752,360
Security Price Change	(3,343)
Total Fair Value Measurement Gain/(Loss)	(3,343)
Mortgage Banking [Member] | Level 2 [Member] | Fair Value, Measurements, Recurring [Member] | Mortgages Held for Sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notional or Principal Amount	212,441
Assumed Gain/(Loss) From Loan Sale	(979)
Interest Rate Movement Effect	(409)
Servicing Rights Value	2,380
Total Fair Value Measurement Gain/(Loss)	$ 992