Derivative Financial Instruments - Summary of Derivative Financial Instruments (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2015
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Interest rate lock commitments	$ 11,800	$ 7,900
Derivative Liabilities | Interest rate lock commitments | Other liabilities
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Notional Amount		2,108	$ 555
Estimated Fair Value		14	6
Derivative Liabilities | Forward contracts to sell mortgage loans | Other liabilities
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Notional Amount		16,000	24,000
Estimated Fair Value		174	90
Derivative Liabilities | Interest rate swap contacts | Other liabilities
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Notional Amount		0	78,433
Estimated Fair Value		0	2,081
Derivative Assets | Interest rate lock commitments | Other assets
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Notional Amount		14,633	18,605
Estimated Fair Value		154	189
Derivative Assets | Forward contracts to sell mortgage loans | Other assets
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Notional Amount		4,000	0
Estimated Fair Value		2	0
Derivative Assets | Interest rate swap contacts | Other assets
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Notional Amount		0	78,433
Estimated Fair Value		$ 0	$ 2,081