Fair Value of Financial Instruments - Fair Value Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Securities available for sale, fair value	$ 761,221	$ 647,974
Collateralized Mortgage Backed Securities [Member]
Securities available for sale, fair value	518,781	404,460
Other Securities [Member]
Securities available for sale, fair value	1,342	1,295
Fair Value, Measurements, Recurring [Member]
Total assets	770,587	649,293
Financial and Nonfinancial Liabilities, Fair Value Disclosure	83,806	104,123
Fair Value, Measurements, Recurring [Member] \| Collateralized Mortgage Backed Securities [Member]
Securities available for sale, fair value	518,781	404,460
Fair Value, Measurements, Recurring [Member] \| Other Securities [Member]
Securities available for sale, fair value	242,440	243,514
Fair Value, Measurements, Recurring [Member] \| Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	9,366	1,319
Interest Rate Swaps, Net Amount	39,094	60,987
Fair Value, Measurements, Recurring [Member] \| Junior Subordinated Debentures [Member]
Borrowings	44,712	43,136
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Total assets	12,525	12,703
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Collateralized Mortgage Backed Securities [Member]
Securities available for sale, fair value	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Other Securities [Member]
Securities available for sale, fair value	12,525	12,703
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	0	0
Interest Rate Swaps, Net Amount	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Junior Subordinated Debentures [Member]
Borrowings	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Total assets	756,720	635,295
Financial and Nonfinancial Liabilities, Fair Value Disclosure	39,094	60,987
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Collateralized Mortgage Backed Securities [Member]
Securities available for sale, fair value	518,781	404,460
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Other Securities [Member]
Securities available for sale, fair value	228,573	229,516
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	9,366	1,319
Interest Rate Swaps, Net Amount	39,094	60,987
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Junior Subordinated Debentures [Member]
Borrowings	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Total assets	1,342	1,295
Financial and Nonfinancial Liabilities, Fair Value Disclosure	44,712	43,136
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Collateralized Mortgage Backed Securities [Member]
Securities available for sale, fair value	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Other Securities [Member]
Securities available for sale, fair value	1,342	1,295
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	0	0
Interest Rate Swaps, Net Amount	0	0
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Junior Subordinated Debentures [Member]
Borrowings	44,712	43,136
Fair Value, Measurements, Nonrecurring [Member]
Total assets	11,388	11,980
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Total assets	0	0
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Total assets	0	0
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Total assets	$ 11,388	$ 11,980

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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