Fair Value Measurements - Summary of Financial Instruments Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets
Securities available for sale	$ 945,660	$ 912,429
Estimate of Fair Value Measurement [Member]
Assets
State tax credits held for sale	37,802	39,925
Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	23,445	15,161
Obligations of states and political subdivisions
Assets
Securities available for sale	403,557	344,232
Agency mortgage-backed securities
Assets
Securities available for sale	492,081	526,572
U.S. Treasury bills
Assets
Securities available for sale	11,409	11,466
Corporate debt securities
Assets
Securities available for sale	15,168	14,998
Recurring basis \| Estimate of Fair Value Measurement [Member]
Assets
Securities available for sale	945,660	912,429
Derivatives	20,271	28,703
Total assets	965,931	941,132
Liabilities
Derivatives	24,799	34,967
Total liabilities	24,799	34,967
Recurring basis \| Obligations of U.S. Government-sponsored enterprises \| Estimate of Fair Value Measurement [Member]
Assets
Securities available for sale	23,445	15,161
Recurring basis \| Obligations of states and political subdivisions \| Estimate of Fair Value Measurement [Member]
Assets
Securities available for sale	403,557	344,232
Recurring basis \| Agency mortgage-backed securities \| Estimate of Fair Value Measurement [Member]
Assets
Securities available for sale	492,081	526,572
Recurring basis \| U.S. Treasury bills \| Estimate of Fair Value Measurement [Member]
Assets
Securities available for sale	11,409	11,466
Recurring basis \| Corporate debt securities \| Estimate of Fair Value Measurement [Member]
Assets
Securities available for sale	15,168	14,998
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Securities available for sale	0	0
Derivatives	0	0
Total assets	0	0
Liabilities
Derivatives	0	0
Total liabilities	0	0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	0	0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Obligations of states and political subdivisions
Assets
Securities available for sale	0	0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Agency mortgage-backed securities
Assets
Securities available for sale	0	0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| U.S. Treasury bills
Assets
Securities available for sale	0	0
Recurring basis \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Corporate debt securities
Assets
Securities available for sale	0	0
Recurring basis \| Significant Other Observable Inputs (Level 2)
Assets
Securities available for sale	945,660	912,429
Derivatives	20,271	28,703
Total assets	965,931	941,132
Liabilities
Derivatives	24,799	34,967
Total liabilities	24,799	34,967
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	23,445	15,161
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Obligations of states and political subdivisions
Assets
Securities available for sale	403,557	344,232
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Agency mortgage-backed securities
Assets
Securities available for sale	492,081	526,572
Recurring basis \| Significant Other Observable Inputs (Level 2) \| U.S. Treasury bills
Assets
Securities available for sale	11,409	11,466
Recurring basis \| Significant Other Observable Inputs (Level 2) \| Corporate debt securities
Assets
Securities available for sale	15,168	14,998
Recurring basis \| Significant Unobservable Inputs (Level 3)
Assets
Securities available for sale	0	0
Derivatives	0	0
Total assets	0	0
Liabilities
Derivatives	0	0
Total liabilities	0	0
Recurring basis \| Significant Unobservable Inputs (Level 3) \| Obligations of U.S. Government-sponsored enterprises
Assets
Securities available for sale	0	0
Recurring basis \| Significant Unobservable Inputs (Level 3) \| Obligations of states and political subdivisions
Assets
Securities available for sale	0	0
Recurring basis \| Significant Unobservable Inputs (Level 3) \| Agency mortgage-backed securities
Assets
Securities available for sale	0	0
Recurring basis \| Significant Unobservable Inputs (Level 3) \| U.S. Treasury bills
Assets
Securities available for sale	0	0
Recurring basis \| Significant Unobservable Inputs (Level 3) \| Corporate debt securities
Assets
Securities available for sale	$ 0	$ 0

State Tax Credits Held For Sale, Fair Value Disclosure

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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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Fair value of financial and nonfinancial obligations.

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