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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	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Mar. 31, 2019	Dec. 31, 2018	Jun. 30, 2018
Assets:
Securities available-for-sale	$ 488,422	$ 488,422		$ 541,248
Mortgage servicing rights	5,361			7,357
US Treasury Securities [Member]
Assets:
Securities available-for-sale			$ 4,038	3,923
US Government Corporations and Agencies Securities [Member]
Assets:
Securities available-for-sale			9,143	10,951
Mortgage Backed Securities, Issued by US Government Agencies [Member]
Assets:
Securities available-for-sale			$ 16,940
US States and Political Subdivisions Debt Securities [Member]
Assets and liabilities measured at fair value on a recurring basis
Purchases	17,643	$ 20,421
Assets:
Securities available-for-sale	238,727			274,067
Collateralized Mortgage Obligations [Member]
Assets:
Securities available-for-sale	64,121			64,429
Asset-backed Securities [Member]
Assets:
Securities available-for-sale	83,182			109,514
Collateralized loan obligations
Assets:
Securities available-for-sale	72,271			64,289
Fair Value, Inputs, Level 1 [Member]
Assets:
Securities available-for-sale	4,038			3,923
Fair Value, Inputs, Level 2 [Member]
Assets:
Securities available-for-sale	478,511			529,160
Loans held-for-sale	5,592			2,984
Liabilities:
Other liabilities	4,696			58
Fair Value, Inputs, Level 3 [Member]
Assets:
Securities available-for-sale	5,873			8,165	$ 9,500
Mortgage servicing rights	5,361			7,357
Fair Value, Inputs, Level 3 [Member] \| US States and Political Subdivisions Debt Securities [Member]
Assets:
Securities available-for-sale	5,900
Fair Value, Inputs, Level 3 [Member] \| Collateralized Mortgage Obligations [Member]
Assets:
Securities available-for-sale					$ 1,600
Fair Value, Measurements, Recurring [Member]
Assets:
Securities available-for-sale				10,951
Total financial assets	503,584			552,420
Liabilities:
Total	8,532			756
Fair Value, Measurements, Recurring [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Loans held-for-sale	5,592			2,984
Mortgage servicing rights	5,361			7,357
Fair Value, Measurements, Recurring [Member] \| Interest Rate Swap [Member]
Liabilities:
Other liabilities	8,532			756
Fair Value, Measurements, Recurring [Member] \| Interest Rate Swap [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Other assets	3,756			672
Fair Value, Measurements, Recurring [Member] \| Forward Contracts [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Other assets	453			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	4,038
Fair Value, Measurements, Recurring [Member] \| US Government Corporations and Agencies Securities [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	9,143
Fair Value, Measurements, Recurring [Member] \| Mortgage Backed Securities, Issued by US Government Agencies [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	16,940			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	238,727			274,067
Fair Value, Measurements, Recurring [Member] \| Collateralized Mortgage Obligations [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	64,121			64,429
Fair Value, Measurements, Recurring [Member] \| Asset-backed Securities [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	83,182			109,514
Fair Value, Measurements, Recurring [Member] \| Collateralized loan obligations \| Finite-Lived Intangible Assets [Member]
Assets:
Securities available-for-sale	72,271			64,289
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Assets:
Total financial assets	4,038			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	4,038
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Assets:
Securities available-for-sale				10,951
Total financial assets	488,312			532,975
Liabilities:
Total	8,532			756
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Loans held-for-sale	5,592			2,984
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Liabilities:
Other liabilities	8,532			756
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Other assets	3,756			672
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Forward Contracts [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Other assets	453			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	9,143
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	16,940			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	232,854			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	64,121			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	83,182			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	72,271			64,289
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Assets:
Total financial assets	11,234			15,522
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Finite-Lived Intangible Assets [Member]
Assets:
Mortgage servicing rights	5,361			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	$ 5,873			$ 8,165