Goodwill and Core Deposit Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Mar. 31, 2017
Goodwill
Beginning of period	$ 85,291	$ 85,291	$ 85,291
End of the period	85,291		85,291
Core Deposit Intangibles RollForward
Beginning of period	9,975	11,562	11,562
Less amortization	(380)	(402)	(1,587)
End of period	9,595		9,975
Amortization of Intangible Assets	380	402	1,587
Expected future amortization expense
Finite-Lived Intangible Assets, Net, Total	9,975	11,562	$ 11,562	$ 9,595
Core deposit intangibles
Core Deposit Intangibles RollForward
Less amortization	(380)	(402)
End of period	9,595
Amortization of Intangible Assets	380	$ 402
Expected future amortization expense
2017				1,092
2018				1,196
2019				1,080
2020				992
2021				905
Thereafter				4,330
Finite-Lived Intangible Assets, Net, Total	$ 9,595			$ 9,595
Core deposit intangibles | Minimum
Core Deposit Intangibles RollForward
Finite-Lived Intangible Asset, Useful Life	2 years
Core deposit intangibles | Maximum
Core Deposit Intangibles RollForward
Finite-Lived Intangible Asset, Useful Life	17 years