Fair Value Measurements - General Disclosures (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	$ 2,946,055	$ 3,981,251
Equity securities	19,520	13,571
Loans held for sale (2022 at LOCOM, 2021 at fair value)	6,765	23,875
U.S. Treasury securities
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	157,508	165,762
Obligations of U.S. government corporations and agencies
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	34,301	38,470
Obligations of states and political subdivisions
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	299,592	306,869
Asset-backed securities
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	488,604	492,186
Commercial mortgage-backed securities
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	107,502	614,998
Residential mortgage-backed securities
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	1,575,376	2,069,313
Corporate debt securities
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	283,172	293,653
Recurring basis
Financial assets and financial liabilities measured at fair value
Equity securities	19,520
Loans held for sale (2022 at LOCOM, 2021 at fair value)		23,875
Recurring basis \| Derivative assets
Financial assets and financial liabilities measured at fair value
Derivative asset	17,573	20,314
Recurring basis \| Derivative liabilities
Financial assets and financial liabilities measured at fair value
Derivative liability	25,384	21,501
Recurring basis \| U.S. Treasury securities
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	157,508	165,762
Recurring basis \| Obligations of U.S. government corporations and agencies
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	34,301	38,470
Recurring basis \| Obligations of states and political subdivisions
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	299,592	306,869
Recurring basis \| Asset-backed securities
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	488,604	492,186
Recurring basis \| Commercial mortgage-backed securities
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	107,502	614,998
Recurring basis \| Residential mortgage-backed securities
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	1,575,376	2,069,313
Recurring basis \| Corporate debt securities
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	283,172	293,653
Recurring basis \| Securities Equity Investments [Member]
Financial assets and financial liabilities measured at fair value
Equity securities		13,571
Recurring basis \| Level 1
Financial assets and financial liabilities measured at fair value
Equity securities	5,948
Recurring basis \| Level 2
Financial assets and financial liabilities measured at fair value
Equity securities	13,572
Loans held for sale (2022 at LOCOM, 2021 at fair value)		23,875
Recurring basis \| Level 2 \| Derivative assets
Financial assets and financial liabilities measured at fair value
Derivative asset	17,568	20,314
Recurring basis \| Level 2 \| Derivative liabilities
Financial assets and financial liabilities measured at fair value
Derivative liability	25,384	21,501
Recurring basis \| Level 2 \| U.S. Treasury securities
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	157,508	165,762
Recurring basis \| Level 2 \| Obligations of U.S. government corporations and agencies
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	34,301	38,470
Recurring basis \| Level 2 \| Obligations of states and political subdivisions
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	299,592	306,869
Recurring basis \| Level 2 \| Asset-backed securities
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	488,604	492,186
Recurring basis \| Level 2 \| Commercial mortgage-backed securities
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	107,502	614,998
Recurring basis \| Level 2 \| Residential mortgage-backed securities
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	1,575,376	2,069,313
Recurring basis \| Level 2 \| Corporate debt securities
Financial assets and financial liabilities measured at fair value
Debt securities available for sale	283,172	293,653
Recurring basis \| Level 2 \| Securities Equity Investments [Member]
Financial assets and financial liabilities measured at fair value
Equity securities		$ 13,571
Recurring basis \| Level 3 \| Derivative assets
Financial assets and financial liabilities measured at fair value
Derivative asset	$ 5

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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