Fair Value Measurements - Recurring (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Assets:
Securities available-for-sale	$ 484,648	$ 541,248
Mortgage servicing rights	5,935	7,357
US Treasury Securities [Member]
Assets:
Securities available-for-sale	4,036	3,923
US Government Corporations and Agencies Securities [Member]
Assets:
Securities available-for-sale		10,951
US States and Political Subdivisions Debt Securities [Member]
Assets and liabilities measured at fair value on a recurring basis
Purchases	17,938	22,046
Assets:
Securities available-for-sale	249,175	274,067
Collateralized Mortgage Obligations [Member]
Assets:
Securities available-for-sale	57,984	64,429
Asset-backed Securities [Member]
Assets:
Securities available-for-sale	81,844	109,514
Collateralized loan obligations
Assets:
Securities available-for-sale	66,684	64,289
Fair Value, Inputs, Level 1 [Member]
Assets:
Securities available-for-sale	4,036	3,923
Fair Value, Inputs, Level 2 [Member]
Assets:
Securities available-for-sale	475,193	529,160
Loans held-for-sale	3,061	2,984
Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Liabilities:
Other liabilities	3,101	58
Level 3
Assets:
Securities available-for-sale	5,419	8,165
Recurring
Assets:
Loans held-for-sale	3,061	2,984
Mortgage servicing rights	5,935	7,357
Total financial assets	496,665	552,420
Liabilities:
Total	5,974	756
Recurring \| Interest Rate Swap [Member]
Assets:
Other assets	2,771	672
Liabilities:
Other liabilities	5,974	756
Recurring \| Forward Contracts [Member]
Assets:
Other assets	250	159
Recurring \| US Treasury Securities [Member]
Assets:
Securities available-for-sale	4,036	3,923
Recurring \| US Government Corporations and Agencies Securities [Member]
Assets:
Securities available-for-sale	8,337	10,951
Recurring \| Mortgage Backed Securities, Issued by US Government Agencies [Member]
Assets:
Securities available-for-sale	16,588	14,075
Recurring \| US States and Political Subdivisions Debt Securities [Member]
Assets:
Securities available-for-sale	249,175	274,067
Recurring \| Collateralized Mortgage Obligations [Member]
Assets:
Securities available-for-sale	57,984	64,429
Recurring \| Asset-backed Securities [Member]
Assets:
Securities available-for-sale	81,844	109,514
Recurring \| Collateralized loan obligations
Assets:
Securities available-for-sale	66,684	64,289
Recurring \| Fair Value, Inputs, Level 1 [Member]
Assets:
Total financial assets	4,036	3,923
Recurring \| Fair Value, Inputs, Level 1 [Member] \| US Treasury Securities [Member]
Assets:
Securities available-for-sale	4,036	3,923
Recurring \| Fair Value, Inputs, Level 2 [Member]
Assets:
Loans held-for-sale	3,061	2,984
Total financial assets	481,275	532,975
Liabilities:
Total	5,974	756
Recurring \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Assets:
Other assets	2,771	672
Liabilities:
Other liabilities	5,974	756
Recurring \| Fair Value, Inputs, Level 2 [Member] \| Forward Contracts [Member]
Assets:
Other assets	250	159
Recurring \| Fair Value, Inputs, Level 2 [Member] \| US Government Corporations and Agencies Securities [Member]
Assets:
Securities available-for-sale	8,337	10,951
Recurring \| Fair Value, Inputs, Level 2 [Member] \| Mortgage Backed Securities, Issued by US Government Agencies [Member]
Assets:
Securities available-for-sale	16,588	14,075
Recurring \| Fair Value, Inputs, Level 2 [Member] \| US States and Political Subdivisions Debt Securities [Member]
Assets:
Securities available-for-sale	243,756	265,902
Recurring \| Fair Value, Inputs, Level 2 [Member] \| Collateralized Mortgage Obligations [Member]
Assets:
Securities available-for-sale	57,984	64,429
Recurring \| Fair Value, Inputs, Level 2 [Member] \| Asset-backed Securities [Member]
Assets:
Securities available-for-sale	81,844	109,514
Recurring \| Fair Value, Inputs, Level 2 [Member] \| Collateralized loan obligations
Assets:
Securities available-for-sale	66,684	64,289
Recurring \| Level 3
Assets:
Mortgage servicing rights	5,935	7,357
Total financial assets	11,354	15,522
Recurring \| Level 3 \| US States and Political Subdivisions Debt Securities [Member]
Assets:
Securities available-for-sale	$ 5,419	$ 8,165

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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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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