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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial and nonfinancial obligations.

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Fair Value Measurements - Recurring (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Assets:
Securities available-for-sale	$ 509,090	$ 509,090	$ 541,248
Mortgage servicing rights	6,715		7,357
US Treasury Securities [Member]
Assets:
Securities available-for-sale	3,960		3,923
US Government Corporations and Agencies Securities [Member]
Assets:
Securities available-for-sale	10,360		10,951
Mortgage Backed Securities, Issued by US Government Agencies [Member]
Assets:
Securities available-for-sale	15,306
US States and Political Subdivisions Debt Securities [Member]
Assets and liabilities measured at fair value on a recurring basis
Purchases	11,325	13,085
Assets:
Securities available-for-sale	281,172		274,067
Collateralized Mortgage Obligations [Member]
Assets:
Securities available-for-sale	64,330		64,429
Asset-backed Securities [Member]
Assets:
Securities available-for-sale	70,811		109,514
Collateralized loan obligations
Assets:
Securities available-for-sale	63,151		64,289
Fair Value, Inputs, Level 1 [Member]
Assets:
Securities available-for-sale	3,960		3,923
Fair Value, Inputs, Level 2 [Member]
Assets:
Securities available-for-sale	485,574		529,160
Loans held-for-sale	2,134		2,984
Liabilities:
Other liabilities	1,131		58
Fair Value, Inputs, Level 3 [Member]
Assets:
Securities available-for-sale	19,556	26,500	8,165
Mortgage servicing rights	6,715		7,357
Fair Value, Inputs, Level 3 [Member] \| US States and Political Subdivisions Debt Securities [Member]
Assets:
Securities available-for-sale	19,600
Fair Value, Inputs, Level 3 [Member] \| Collateralized Mortgage Obligations [Member]
Assets:
Securities available-for-sale		$ 2,100
Fair Value, Measurements, Recurring [Member]
Assets:
Securities available-for-sale			10,951
Total financial assets	518,848		552,420
Liabilities:
Total	742		672
Fair Value, Measurements, Recurring [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Loans held-for-sale	2,134		2,984
Mortgage servicing rights	6,715		7,357
Fair Value, Measurements, Recurring [Member] \| Interest Rate Swap [Member]
Liabilities:
Other liabilities	742		672
Fair Value, Measurements, Recurring [Member] \| Interest Rate Swap [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Other assets	742		672
Fair Value, Measurements, Recurring [Member] \| Forward Contracts [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Other assets	167		159
Fair Value, Measurements, Recurring [Member] \| US Treasury Securities [Member]
Assets:
Securities available-for-sale			3,923
Fair Value, Measurements, Recurring [Member] \| US Treasury Securities [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	3,960
Fair Value, Measurements, Recurring [Member] \| US Government Corporations and Agencies Securities [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	10,360
Fair Value, Measurements, Recurring [Member] \| Mortgage Backed Securities, Issued by US Government Agencies [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	15,306		14,075
Fair Value, Measurements, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	281,172		274,067
Fair Value, Measurements, Recurring [Member] \| Collateralized Mortgage Obligations [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	64,330		64,429
Fair Value, Measurements, Recurring [Member] \| Asset-backed Securities [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	70,811		109,514
Fair Value, Measurements, Recurring [Member] \| Collateralized loan obligations \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	63,151		64,289
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Assets:
Total financial assets	3,960		3,923
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| US Treasury Securities [Member]
Assets:
Securities available-for-sale			3,923
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| US Treasury Securities [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	3,960
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Assets:
Securities available-for-sale			10,951
Total financial assets	488,617		532,975
Liabilities:
Total	742		672
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Loans held-for-sale	2,134		2,984
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Liabilities:
Other liabilities	742		672
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Other assets	742		672
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Forward Contracts [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Other assets	167		159
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| US Government Corporations and Agencies Securities [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	10,360
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Mortgage Backed Securities, Issued by US Government Agencies [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	15,306		14,075
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	261,616		265,902
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Collateralized Mortgage Obligations [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	64,330		64,429
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Asset-backed Securities [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	70,811		109,514
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Collateralized loan obligations \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	63,151		64,289
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Assets:
Total financial assets	26,271		15,522
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Mortgage servicing rights	6,715		7,357
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	$ 19,556		$ 8,165