v3.21.1

Fair Value of Financial Instruments and Fair Value Measurements - Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	$ 1,896,894	$ 1,657,381
Derivative assets	6,894	10,796
Mortgage servicing rights	5,928	5,137
U.S. Government agencies and corporations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	340	361
State and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	673,923	628,346
Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	79,005	94,018
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	427,645	368,820
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative assets	6,894	10,796
Mortgage servicing rights	5,928	5,137
Derivative liabilities	7,694	13,267
Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative assets	0	0
Mortgage servicing rights	0	0
Derivative liabilities	0	0
Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative assets	6,894	10,796
Mortgage servicing rights	5,928	5,137
Derivative liabilities	7,694	13,267
Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Derivative assets	0	0
Mortgage servicing rights	0	0
Derivative liabilities	0	0
Recurring | U.S. Government agencies and corporations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	340	361
Recurring | U.S. Government agencies and corporations | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	0	0
Recurring | U.S. Government agencies and corporations | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	340	361
Recurring | U.S. Government agencies and corporations | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	0	0
Recurring | State and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	673,923	628,346
Recurring | State and political subdivisions | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	0	0
Recurring | State and political subdivisions | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	673,923	628,346
Recurring | State and political subdivisions | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	0	0
Recurring | Mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	79,005	94,018
Recurring | Mortgage-backed securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	0	0
Recurring | Mortgage-backed securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	79,005	94,018
Recurring | Mortgage-backed securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	0	0
Recurring | Collateralized mortgage obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	715,981	565,836
Recurring | Collateralized mortgage obligations | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	0	0
Recurring | Collateralized mortgage obligations | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	715,981	565,836
Recurring | Collateralized mortgage obligations | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	0	0
Recurring | Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	427,645	368,820
Recurring | Corporate debt securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	0	0
Recurring | Corporate debt securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	427,645	368,820
Recurring | Corporate debt securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Debt securities available for sale	$ 0	$ 0

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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 of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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