Fair Value Measurement and Fair Value of Financial Instruments - Schedule Of Financial Assets (Liabilities) Measured At Fair Value On a Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Affordable housing partnership, tax credit and CRA investments, net:
Total affordable housing partnership, tax credit and CRA investments, net	$ 956,428	$ 905,036
Derivative
Derivative assets - Fair value	554,460	610,920
Net derivative assets	112,650	298,128
Derivative liabilities - Fair value	613,145	613,314
Net derivative liabilities	503,955	537,144
Fair Value	8,923,528	6,188,337
Government National Mortgage Association (GNMA)
Derivative
Fair Value	5,200,000	1,200,000
U.S. Treasury securities
Derivative
Fair Value	623,757	1,060,375
U.S. government agency and U.S. government-sponsored enterprise debt securities
Derivative
Fair Value	260,388	364,446
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities
Derivative
Fair Value	444,847	468,259
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities
Derivative
Fair Value	5,718,818	1,727,594
Municipal securities
Derivative
Fair Value	256,563	261,016
Non-agency commercial mortgage-backed securities
Derivative
Fair Value	320,637	367,516
Non-agency residential mortgage-backed securities
Derivative
Fair Value	474,618	553,671
Corporate debt securities
Derivative
Fair Value	507,130	502,425
Foreign government bonds
Derivative
Fair Value	233,724	227,874
Asset-backed securities
Derivative
Fair Value	38,593	42,300
Collateralized loan obligations (“CLOs”)
Derivative
Fair Value	44,453	612,861
Fair Value, Measurements, Recurring
Available-for-sale debt securities
Fair Value	8,923,528	6,188,337
Affordable housing partnership, tax credit and CRA investments, net:
Equity securities	24,602	24,659
Total affordable housing partnership, tax credit and CRA investments, net	24,602	24,659
Other assets
Equity securities	471
Total other assets	471
Derivative
Derivative assets - Fair value	554,460	610,920
Netting adjustments	(441,810)	(312,792)
Net derivative assets	112,650	298,128
Derivative liabilities - Fair value	613,145	613,314
Netting adjustments	(109,190)	(76,170)
Net derivative liabilities	503,955	537,144
Fair Value, Measurements, Recurring \| Interest rate contracts
Derivative
Derivative assets - Fair value	459,590	473,907
Derivative liabilities - Fair value	501,514	433,936
Fair Value, Measurements, Recurring \| Foreign exchange contracts
Derivative
Derivative assets - Fair value	33,684	57,072
Derivative liabilities - Fair value	25,598	42,564
Fair Value, Measurements, Recurring \| Equity contracts
Derivative
Derivative assets - Fair value	240	336
Derivative liabilities - Fair value	15,119	15,119
Fair Value, Measurements, Recurring \| Credit contracts
Derivative
Derivative assets - Fair value		1
Derivative liabilities - Fair value	14	25
Fair Value, Measurements, Recurring \| Commodity contracts
Derivative
Derivative assets - Fair value	60,946	79,604
Derivative liabilities - Fair value	70,900	121,670
Fair Value, Measurements, Recurring \| U.S. Treasury securities
Available-for-sale debt securities
Fair Value	623,757	1,060,375
Fair Value, Measurements, Recurring \| U.S. government agency and U.S. government-sponsored enterprise debt securities
Available-for-sale debt securities
Fair Value	260,388	364,446
Fair Value, Measurements, Recurring \| U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities
Available-for-sale debt securities
Fair Value	444,847	468,259
Fair Value, Measurements, Recurring \| U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities
Available-for-sale debt securities
Fair Value	5,718,818	1,727,594
Fair Value, Measurements, Recurring \| Municipal securities
Available-for-sale debt securities
Fair Value	256,563	261,016
Fair Value, Measurements, Recurring \| Non-agency commercial mortgage-backed securities
Available-for-sale debt securities
Fair Value	320,637	367,516
Fair Value, Measurements, Recurring \| Non-agency residential mortgage-backed securities
Available-for-sale debt securities
Fair Value	474,618	553,671
Fair Value, Measurements, Recurring \| Corporate debt securities
Available-for-sale debt securities
Fair Value	507,130	502,425
Fair Value, Measurements, Recurring \| Foreign government bonds
Available-for-sale debt securities
Fair Value	233,724	227,874
Fair Value, Measurements, Recurring \| Asset-backed securities
Available-for-sale debt securities
Fair Value	38,593	42,300
Fair Value, Measurements, Recurring \| Collateralized loan obligations (“CLOs”)
Available-for-sale debt securities
Fair Value	44,453	612,861
Fair Value, Measurements, Recurring \| Level 1
Available-for-sale debt securities
Fair Value	623,757	1,060,375
Affordable housing partnership, tax credit and CRA investments, net:
Equity securities	20,443	20,509
Total affordable housing partnership, tax credit and CRA investments, net	20,443	20,509
Other assets
Total other assets	471
Derivative
Derivative assets - Fair value	0	0
Netting adjustments	0	0
Net derivative assets	0	0
Derivative liabilities - Fair value	0	0
Netting adjustments	0	0
Net derivative liabilities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Interest rate contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Foreign exchange contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Equity contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Credit contracts
Derivative
Derivative assets - Fair value		0
Derivative liabilities - Fair value	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Commodity contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Fair Value, Measurements, Recurring \| Level 1 \| U.S. Treasury securities
Available-for-sale debt securities
Fair Value	623,757	1,060,375
Fair Value, Measurements, Recurring \| Level 1 \| U.S. government agency and U.S. government-sponsored enterprise debt securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 1 \| U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 1 \| U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Municipal securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Non-agency commercial mortgage-backed securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Non-agency residential mortgage-backed securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Corporate debt securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Foreign government bonds
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Asset-backed securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Collateralized loan obligations (“CLOs”)
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 2
Available-for-sale debt securities
Fair Value	8,299,771	5,127,962
Affordable housing partnership, tax credit and CRA investments, net:
Equity securities	4,159	4,150
Total affordable housing partnership, tax credit and CRA investments, net	4,159	4,150
Other assets
Equity securities	0
Total other assets	0
Derivative
Derivative assets - Fair value	554,220	610,584
Netting adjustments	(441,810)	(312,792)
Net derivative assets	112,410	297,792
Derivative liabilities - Fair value	598,026	598,195
Netting adjustments	(109,190)	(76,170)
Net derivative liabilities	488,836	522,025
Fair Value, Measurements, Recurring \| Level 2 \| Interest rate contracts
Derivative
Derivative assets - Fair value	459,590	473,907
Derivative liabilities - Fair value	501,514	433,936
Fair Value, Measurements, Recurring \| Level 2 \| Foreign exchange contracts
Derivative
Derivative assets - Fair value	33,684	57,072
Derivative liabilities - Fair value	25,598	42,564
Fair Value, Measurements, Recurring \| Level 2 \| Equity contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Fair Value, Measurements, Recurring \| Level 2 \| Credit contracts
Derivative
Derivative assets - Fair value		1
Derivative liabilities - Fair value	14	25
Fair Value, Measurements, Recurring \| Level 2 \| Commodity contracts
Derivative
Derivative assets - Fair value	60,946	79,604
Derivative liabilities - Fair value	70,900	121,670
Fair Value, Measurements, Recurring \| Level 2 \| U.S. Treasury securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 2 \| U.S. government agency and U.S. government-sponsored enterprise debt securities
Available-for-sale debt securities
Fair Value	260,388	364,446
Fair Value, Measurements, Recurring \| Level 2 \| U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities
Available-for-sale debt securities
Fair Value	444,847	468,259
Fair Value, Measurements, Recurring \| Level 2 \| U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities
Available-for-sale debt securities
Fair Value	5,718,818	1,727,594
Fair Value, Measurements, Recurring \| Level 2 \| Municipal securities
Available-for-sale debt securities
Fair Value	256,563	261,016
Fair Value, Measurements, Recurring \| Level 2 \| Non-agency commercial mortgage-backed securities
Available-for-sale debt securities
Fair Value	320,637	367,516
Fair Value, Measurements, Recurring \| Level 2 \| Non-agency residential mortgage-backed securities
Available-for-sale debt securities
Fair Value	474,618	553,671
Fair Value, Measurements, Recurring \| Level 2 \| Corporate debt securities
Available-for-sale debt securities
Fair Value	507,130	502,425
Fair Value, Measurements, Recurring \| Level 2 \| Foreign government bonds
Available-for-sale debt securities
Fair Value	233,724	227,874
Fair Value, Measurements, Recurring \| Level 2 \| Asset-backed securities
Available-for-sale debt securities
Fair Value	38,593	42,300
Fair Value, Measurements, Recurring \| Level 2 \| Collateralized loan obligations (“CLOs”)
Available-for-sale debt securities
Fair Value	44,453	612,861
Fair Value, Measurements, Recurring \| Level 3
Available-for-sale debt securities
Fair Value	0	0
Affordable housing partnership, tax credit and CRA investments, net:
Equity securities	0	0
Total affordable housing partnership, tax credit and CRA investments, net	0	0
Other assets
Equity securities	0
Total other assets	0
Derivative
Derivative assets - Fair value	240	336
Netting adjustments	0	0
Net derivative assets	240	336
Derivative liabilities - Fair value	15,119	15,119
Netting adjustments	0	0
Net derivative liabilities	15,119	15,119
Fair Value, Measurements, Recurring \| Level 3 \| Interest rate contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Foreign exchange contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Equity contracts
Derivative
Derivative assets - Fair value	240	336
Derivative liabilities - Fair value	15,119	15,119
Fair Value, Measurements, Recurring \| Level 3 \| Credit contracts
Derivative
Derivative assets - Fair value		0
Derivative liabilities - Fair value	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Commodity contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Fair Value, Measurements, Recurring \| Level 3 \| U.S. Treasury securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 3 \| U.S. government agency and U.S. government-sponsored enterprise debt securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 3 \| U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 3 \| U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Municipal securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Non-agency commercial mortgage-backed securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Non-agency residential mortgage-backed securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Corporate debt securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Foreign government bonds
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Asset-backed securities
Available-for-sale debt securities
Fair Value	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Collateralized loan obligations (“CLOs”)
Available-for-sale debt securities
Fair Value	$ 0	$ 0

Equity Securities Fairvalue Other Assets

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- Definition

Represents the net amount of investments in the projects that qualify for Community Reinvestment Act (CRA) credits or other types of tax credits.

+ References

No definition available.

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No definition available.

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- Definition

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

+ References

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- Definition

Amount excluding accrued interest, 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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- Definition

Fair value, before 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 elected not to be offset.

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- Definition

Fair value of liability associated with 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, and obligation to return cash collateral under master netting arrangements.

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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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