Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	10 Months Ended	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Goodwill, adjustments during measurement period		$ 94	$ 0
Goodwill acquired		0	115,944
Acquisition of core deposits	$ 4,500		4,500
Acquisition of wealth management relationships	100		100
Acquisition of insurance contract relationships	300		300
Finite-lived Intangible Assets Acquired		0	5,713
Amortization expense on finite-lived intangible assets		1,615	1,818	$ 1,129
Integrity Bancshares, Inc.
Goodwill [Line Items]
Goodwill, adjustments during measurement period	$ (1,100)	$ 100
Goodwill acquired			115,900
Finite-lived Intangible Assets Acquired			$ 5,700