Fair Value of Financial Instruments - Fair Value Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Securities available for sale, fair value	$ 772,500	$ 822,655
Collateralized Mortgage Backed Securities [Member]
Securities available for sale, fair value	523,849	557,953
Other Securities [Member]
Securities available for sale, fair value	1,332	1,256
Fair Value, Measurements, Recurring [Member]
Total assets	774,852	838,616
Financial and Nonfinancial Liabilities, Fair Value Disclosure	64,037	44,088
Fair Value, Measurements, Recurring [Member] \| Collateralized Mortgage Backed Securities [Member]
Securities available for sale, fair value	523,849	557,953
Fair Value, Measurements, Recurring [Member] \| Other Securities [Member]
Securities available for sale, fair value	248,651	264,702
Fair Value, Measurements, Recurring [Member] \| Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	2,352	15,961
Interest Rate Swaps, Net Amount	19,653	2,239
Fair Value, Measurements, Recurring [Member] \| Junior Subordinated Debentures [Member]
Borrowings	44,384	41,849
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Total assets	12,216	11,586
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	12,216	11,586
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	761,304	825,774
Financial and Nonfinancial Liabilities, Fair Value Disclosure	19,653	2,239
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Collateralized Mortgage Backed Securities [Member]
Securities available for sale, fair value	523,849	557,953
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Other Securities [Member]
Securities available for sale, fair value	235,103	251,860
Fair Value, Measurements, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Interest Rate Swap [Member]
Interest Rate Swaps, Net Amount	2,352	15,961
Interest Rate Swaps, Net Amount	19,653	2,239
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	1,332	1,256
Financial and Nonfinancial Liabilities, Fair Value Disclosure	44,384	41,849
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	1,332	1,256
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	$ 44,384	$ 41,849

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 investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Fair value of financial and nonfinancial obligations.

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