Fair Value Accounting - Financial Instruments Measured At Fair Value On A Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Assets
Total investment securities available for sale	$ 9,678,103	$ 10,918,329
Mutual funds and mutual funds held in rabbi trusts	42,659	43,657
Derivative assets	89,815	191,708
U.S. Treasury securities
Assets
Total investment securities available for sale	471,813	117,838
Mortgage-backed securities issued by U.S. Government agencies
Assets
Total investment securities available for sale	792,749	779,633
Mortgage-backed securities issued by U.S. Government sponsored enterprises
Assets
Total investment securities available for sale	6,895,070	8,012,301
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises
Assets
Total investment securities available for sale	655,127	939,623
Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises
Assets
Total investment securities available for sale	805,945	481,744
Asset-backed securities
Assets
Total investment securities available for sale		514,188
Corporate debt securities and other debt securities
Assets
Total investment securities available for sale	8,601	18,801
Fair Value, Measurements, Recurring
Assets
Total trading securities	8,295	8,391
Total investment securities available for sale	9,678,103	10,918,329
Mortgage loans held for sale	51,136	108,198
Other investments	11,172	12,185
Mutual funds and mutual funds held in rabbi trusts	42,659	43,657
SBA loans servicing asset	2,354	3,233
Derivative assets	89,815	191,708
Liabilities
Securities sold short	3,370	200
Mutual fund held in rabbi trusts	27,944	27,205
Derivative liabilities	342,680	98,602
Fair Value, Measurements, Recurring \| Level 1
Assets
Total trading securities	0	0
Total investment securities available for sale	471,813	117,838
Mortgage loans held for sale	0	0
Other investments	0	0
Mutual funds and mutual funds held in rabbi trusts	42,659	43,657
SBA loans servicing asset	0	0
Derivative assets	0	0
Liabilities
Securities sold short	3,370	0
Mutual fund held in rabbi trusts	27,944	27,205
Derivative liabilities	0	0
Fair Value, Measurements, Recurring \| Level 2
Assets
Total trading securities	8,295	8,391
Total investment securities available for sale	9,206,290	10,800,491
Mortgage loans held for sale	51,136	108,198
Other investments	0	0
Mutual funds and mutual funds held in rabbi trusts	0	0
SBA loans servicing asset	0	0
Derivative assets	89,815	191,708
Liabilities
Securities sold short	0	200
Mutual fund held in rabbi trusts	0	0
Derivative liabilities	339,227	95,067
Fair Value, Measurements, Recurring \| Level 3
Assets
Total trading securities	0	0
Total investment securities available for sale	0	0
Mortgage loans held for sale	0	0
Other investments	11,172	12,185
Mutual funds and mutual funds held in rabbi trusts	0	0
SBA loans servicing asset	2,354	3,233
Derivative assets	0	0
Liabilities
Securities sold short	0	0
Mutual fund held in rabbi trusts	0	0
Derivative liabilities	3,453	3,535
Fair Value, Measurements, Recurring \| U.S. Treasury securities
Assets
Total investment securities available for sale	471,813	117,838
Fair Value, Measurements, Recurring \| U.S. Treasury securities \| Level 1
Assets
Total investment securities available for sale	471,813	117,838
Fair Value, Measurements, Recurring \| U.S. Treasury securities \| Level 2
Assets
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring \| U.S. Treasury securities \| Level 3
Assets
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring \| U.S. Government agency securities
Assets
Total investment securities available for sale	48,798	54,201
Fair Value, Measurements, Recurring \| U.S. Government agency securities \| Level 1
Assets
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring \| U.S. Government agency securities \| Level 2
Assets
Total investment securities available for sale	48,798	54,201
Fair Value, Measurements, Recurring \| U.S. Government agency securities \| Level 3
Assets
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring \| Mortgage-backed securities issued by U.S. Government agencies
Assets
Total trading securities	0	197
Total investment securities available for sale	792,749	779,633
Fair Value, Measurements, Recurring \| Mortgage-backed securities issued by U.S. Government agencies \| Level 1
Assets
Total trading securities	0	0
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring \| Mortgage-backed securities issued by U.S. Government agencies \| Level 2
Assets
Total trading securities	0	197
Total investment securities available for sale	792,749	779,633
Fair Value, Measurements, Recurring \| Mortgage-backed securities issued by U.S. Government agencies \| Level 3
Assets
Total trading securities	0	0
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring \| Mortgage-backed securities issued by U.S. Government sponsored enterprises
Assets
Total investment securities available for sale	6,895,070	8,012,301
Fair Value, Measurements, Recurring \| Mortgage-backed securities issued by U.S. Government sponsored enterprises \| Level 1
Assets
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring \| Mortgage-backed securities issued by U.S. Government sponsored enterprises \| Level 2
Assets
Total investment securities available for sale	6,895,070	8,012,301
Fair Value, Measurements, Recurring \| Mortgage-backed securities issued by U.S. Government sponsored enterprises \| Level 3
Assets
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring \| Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises
Assets
Total trading securities	2,991	671
Total investment securities available for sale	655,127	939,623
Fair Value, Measurements, Recurring \| Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises \| Level 1
Assets
Total trading securities	0	0
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring \| Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises \| Level 2
Assets
Total trading securities	2,991	671
Total investment securities available for sale	655,127	939,623
Fair Value, Measurements, Recurring \| Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises \| Level 3
Assets
Total trading securities	0	0
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring \| Other mortgage-backed securities
Assets
Total trading securities	3,185	0
Fair Value, Measurements, Recurring \| Other mortgage-backed securities \| Level 1
Assets
Total trading securities	0	0
Fair Value, Measurements, Recurring \| Other mortgage-backed securities \| Level 2
Assets
Total trading securities	3,185	0
Fair Value, Measurements, Recurring \| Other mortgage-backed securities \| Level 3
Assets
Total trading securities	0	0
Fair Value, Measurements, Recurring \| State and municipal securities
Assets
Total trading securities	48	560
Fair Value, Measurements, Recurring \| State and municipal securities \| Level 1
Assets
Total trading securities	0	0
Fair Value, Measurements, Recurring \| State and municipal securities \| Level 2
Assets
Total trading securities	48	560
Fair Value, Measurements, Recurring \| State and municipal securities \| Level 3
Assets
Total trading securities	0	0
Fair Value, Measurements, Recurring \| Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises
Assets
Total investment securities available for sale	805,945	481,744
Fair Value, Measurements, Recurring \| Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises \| Level 1
Assets
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring \| Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises \| Level 2
Assets
Total investment securities available for sale	805,945	481,744
Fair Value, Measurements, Recurring \| Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises \| Level 3
Assets
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring \| Asset-backed securities
Assets
Total trading securities	2,071	6,963
Total investment securities available for sale	0	514,188
Fair Value, Measurements, Recurring \| Asset-backed securities \| Level 1
Assets
Total trading securities	0	0
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring \| Asset-backed securities \| Level 2
Assets
Total trading securities	2,071	6,963
Total investment securities available for sale	0	514,188
Fair Value, Measurements, Recurring \| Asset-backed securities \| Level 3
Assets
Total trading securities	0	0
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring \| Corporate debt securities and other debt securities
Assets
Total investment securities available for sale	8,601	18,801
Fair Value, Measurements, Recurring \| Corporate debt securities and other debt securities \| Level 1
Assets
Total investment securities available for sale	0	0
Fair Value, Measurements, Recurring \| Corporate debt securities and other debt securities \| Level 2
Assets
Total investment securities available for sale	8,601	18,801
Fair Value, Measurements, Recurring \| Corporate debt securities and other debt securities \| Level 3
Assets
Total investment securities available for sale	$ 0	$ 0

Mutual Funds And Mutual Funds Held In Rabbi Trusts In Liability

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Mutual Funds and Mutual Funds Held In Rabbi Trusts

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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, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value portion of mortgage loans held-for-sale.

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Amount of investments classified as other.

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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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Fair value portion of liabilities pertaining to principal and customer trading transactions, or which may be incurred with the objective of generating a profit from short-term fluctuations in price as part of an entity's market-making, hedging and proprietary trading. Examples include, but are not limited to, short positions in securities, derivatives and commodities.

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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