Fair Value Measurements - Recurring (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Assets:
Securities available-for-sale	$ 531,057	$ 456,066
Mortgage servicing rights	5,075	5,847
U.S. Treasury
Assets:
Securities available-for-sale		1,509
U.S. government agencies
Assets:
Securities available-for-sale	1,503	1,556
U.S. government agency mortgage-backed
Assets:
Securities available-for-sale	43,723	1,996
States and political subdivisions
Assets:
Securities available-for-sale	22,254	30,526
Corporate bonds
Assets:
Securities available-for-sale	10,730	29,400
Collateralized mortgage obligations
Assets:
Securities available-for-sale	204,390	66,920
Asset-backed securities
Assets:
Securities available-for-sale	140,173	231,908
Collateralized loan obligations
Assets:
Securities available-for-sale	108,284	92,251
Level 1
Assets:
Securities available-for-sale		1,509
Level 2
Assets:
Securities available-for-sale	531,057	454,446
Loans held-for-sale	3,750	2,849
Liabilities:
Other liabilities	4,910	631
Level 3
Assets:
Securities available-for-sale		111
Recurring
Assets:
Total financial assets	540,963	465,064
Liabilities:
Total	5,698	745
Recurring \| Finite-Lived Intangible Assets [Member]
Assets:
Loans held-for-sale	3,750	2,849
Mortgage servicing rights	5,075	5,847
Recurring \| Interest rate swap agreements net of swap credit valuation
Liabilities:
Other liabilities	5,698	745
Recurring \| Interest rate swap agreements net of swap credit valuation \| Finite-Lived Intangible Assets [Member]
Assets:
Other assets	788	114
Recurring \| Forward MBS contracts and forward loan contracts \| Finite-Lived Intangible Assets [Member]
Assets:
Other assets	293	188
Recurring \| U.S. Treasury \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale		1,509
Recurring \| U.S. government agencies \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	1,503	1,556
Recurring \| U.S. government agency mortgage-backed \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	43,723	1,996
Recurring \| States and political subdivisions \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	22,254	30,526
Recurring \| Corporate bonds \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	10,730	29,400
Recurring \| Collateralized mortgage obligations \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	204,390	66,920
Recurring \| Asset-backed securities \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	140,173	231,908
Recurring \| Collateralized loan obligations \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	108,284	92,251
Recurring \| Level 1
Assets:
Total financial assets		1,509
Recurring \| Level 1 \| U.S. Treasury \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale		1,509
Recurring \| Level 2
Assets:
Total financial assets	535,888	457,597
Liabilities:
Total	5,698	745
Recurring \| Level 2 \| Finite-Lived Intangible Assets [Member]
Assets:
Loans held-for-sale	3,750	2,849
Recurring \| Level 2 \| Interest rate swap agreements net of swap credit valuation
Liabilities:
Other liabilities	5,698	745
Recurring \| Level 2 \| Interest rate swap agreements net of swap credit valuation \| Finite-Lived Intangible Assets [Member]
Assets:
Other assets	788	114
Recurring \| Level 2 \| Forward MBS contracts and forward loan contracts \| Finite-Lived Intangible Assets [Member]
Assets:
Other assets	293	188
Recurring \| Level 2 \| U.S. government agencies \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	1,503	1,556
Recurring \| Level 2 \| U.S. government agency mortgage-backed \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	43,723	1,996
Recurring \| Level 2 \| States and political subdivisions \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	22,254	30,415
Recurring \| Level 2 \| Corporate bonds \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	10,730	29,400
Recurring \| Level 2 \| Collateralized mortgage obligations \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	204,390	66,920
Recurring \| Level 2 \| Asset-backed securities \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	140,173	231,908
Recurring \| Level 2 \| Collateralized loan obligations \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	108,284	92,251
Recurring \| Level 3
Assets:
Total financial assets	5,075	5,958
Recurring \| Level 3 \| Finite-Lived Intangible Assets [Member]
Assets:
Mortgage servicing rights	$ 5,075	5,847
Recurring \| Level 3 \| States and political subdivisions \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale		$ 111

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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