Fair Value Measurement and Fair Value of Financial Instruments - Financial Assets and Liabilities Measurement on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Affordable housing partnership, tax credit and CRA investments, net:
Total affordable housing partnership, tax credit and CRA investments, net	$ 933,187	$ 905,036
Derivative
Derivative assets - Fair value	622,238	610,920
Net derivative assets	132,976	298,128
Derivative liabilities - Fair value	693,548	613,314
Net derivative liabilities	558,585	537,144
Fair Value	8,400,468	6,188,337
Government National Mortgage Association (GNMA)
Derivative
Fair Value	4,400,000	1,200,000
U.S. Treasury securities
Derivative
Fair Value	621,094	1,060,375
U.S. government agency and U.S. government-sponsored enterprise debt securities
Derivative
Fair Value	360,802	364,446
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities
Derivative
Fair Value	455,619	468,259
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities
Derivative
Fair Value	4,992,399	1,727,594
Municipal securities
Derivative
Fair Value	258,495	261,016
Non-agency commercial mortgage-backed securities
Derivative
Fair Value	333,996	367,516
Non-agency residential mortgage-backed securities
Derivative
Fair Value	519,657	553,671
Corporate debt securities
Derivative
Fair Value	502,647	502,425
Foreign government bonds
Derivative
Fair Value	227,196	227,874
Asset-backed securities
Derivative
Fair Value	40,712	42,300
Collateralized loan obligations (“CLOs”)
Derivative
Fair Value	87,851	612,861
Fair Value, Measurements, Recurring
Available-for-sale debt securities
Fair Value	8,400,468	6,188,337
Affordable housing partnership, tax credit and CRA investments, net:
Equity securities	24,539	24,659
Total affordable housing partnership, tax credit and CRA investments, net	24,539	24,659
Derivative
Derivative assets - Fair value	622,238	610,920
Netting adjustments	(489,262)	(312,792)
Net derivative assets	132,976	298,128
Derivative liabilities - Fair value	693,548	613,314
Netting adjustments	(134,963)	(76,170)
Net derivative liabilities	558,585	537,144
Fair Value, Measurements, Recurring | Interest rate contracts
Derivative
Derivative assets - Fair value	484,794	473,907
Derivative liabilities - Fair value	518,330	433,936
Fair Value, Measurements, Recurring | Foreign exchange contracts
Derivative
Derivative assets - Fair value	60,499	57,072
Derivative liabilities - Fair value	53,153	42,564
Fair Value, Measurements, Recurring | Equity contracts
Derivative
Derivative assets - Fair value	330	336
Derivative liabilities - Fair value	15,119	15,119
Fair Value, Measurements, Recurring | Commodity contracts
Derivative
Derivative assets - Fair value	76,615	79,604
Derivative liabilities - Fair value	106,930	121,670
Fair Value, Measurements, Recurring | Credit contracts
Derivative
Derivative assets - Fair value		1
Derivative liabilities - Fair value	16	25
Fair Value, Measurements, Recurring | U.S. Treasury securities
Available-for-sale debt securities
Fair Value	621,094	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	360,802	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	455,619	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	4,992,399	1,727,594
Fair Value, Measurements, Recurring | Municipal securities
Available-for-sale debt securities
Fair Value	258,495	261,016
Fair Value, Measurements, Recurring | Non-agency commercial mortgage-backed securities
Available-for-sale debt securities
Fair Value	333,996	367,516
Fair Value, Measurements, Recurring | Non-agency residential mortgage-backed securities
Available-for-sale debt securities
Fair Value	519,657	553,671
Fair Value, Measurements, Recurring | Corporate debt securities
Available-for-sale debt securities
Fair Value	502,647	502,425
Fair Value, Measurements, Recurring | Foreign government bonds
Available-for-sale debt securities
Fair Value	227,196	227,874
Fair Value, Measurements, Recurring | Asset-backed securities
Available-for-sale debt securities
Fair Value	40,712	42,300
Fair Value, Measurements, Recurring | Collateralized loan obligations (“CLOs”)
Available-for-sale debt securities
Fair Value	87,851	612,861
Level 1 | Fair Value, Measurements, Recurring
Available-for-sale debt securities
Fair Value	621,094	1,060,375
Affordable housing partnership, tax credit and CRA investments, net:
Equity securities	20,402	20,509
Total affordable housing partnership, tax credit and CRA investments, net	20,402	20,509
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
Level 1 | Fair Value, Measurements, Recurring | Interest rate contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Level 1 | Fair Value, Measurements, Recurring | Foreign exchange contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Level 1 | Fair Value, Measurements, Recurring | Equity contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Level 1 | Fair Value, Measurements, Recurring | Commodity contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Level 1 | Fair Value, Measurements, Recurring | Credit contracts
Derivative
Derivative assets - Fair value		0
Derivative liabilities - Fair value	0	0
Level 1 | Fair Value, Measurements, Recurring | U.S. Treasury securities
Available-for-sale debt securities
Fair Value	621,094	1,060,375
Level 1 | Fair Value, Measurements, Recurring | U.S. government agency and U.S. government-sponsored enterprise debt securities
Available-for-sale debt securities
Fair Value	0	0
Level 1 | 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	0	0
Level 1 | 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	0	0
Level 1 | Fair Value, Measurements, Recurring | Municipal securities
Available-for-sale debt securities
Fair Value	0	0
Level 1 | Fair Value, Measurements, Recurring | Non-agency commercial mortgage-backed securities
Available-for-sale debt securities
Fair Value	0	0
Level 1 | Fair Value, Measurements, Recurring | Non-agency residential mortgage-backed securities
Available-for-sale debt securities
Fair Value	0	0
Level 1 | Fair Value, Measurements, Recurring | Corporate debt securities
Available-for-sale debt securities
Fair Value	0	0
Level 1 | Fair Value, Measurements, Recurring | Foreign government bonds
Available-for-sale debt securities
Fair Value	0	0
Level 1 | Fair Value, Measurements, Recurring | Asset-backed securities
Available-for-sale debt securities
Fair Value	0	0
Level 1 | Fair Value, Measurements, Recurring | Collateralized loan obligations (“CLOs”)
Available-for-sale debt securities
Fair Value	0	0
Level 2 | Fair Value, Measurements, Recurring
Available-for-sale debt securities
Fair Value	7,779,374	5,127,962
Affordable housing partnership, tax credit and CRA investments, net:
Equity securities	4,137	4,150
Total affordable housing partnership, tax credit and CRA investments, net	4,137	4,150
Derivative
Derivative assets - Fair value	621,908	610,584
Netting adjustments	(489,262)	(312,792)
Net derivative assets	132,646	297,792
Derivative liabilities - Fair value	678,429	598,195
Netting adjustments	(134,963)	(76,170)
Net derivative liabilities	543,466	522,025
Level 2 | Fair Value, Measurements, Recurring | Interest rate contracts
Derivative
Derivative assets - Fair value	484,794	473,907
Derivative liabilities - Fair value	518,330	433,936
Level 2 | Fair Value, Measurements, Recurring | Foreign exchange contracts
Derivative
Derivative assets - Fair value	60,499	57,072
Derivative liabilities - Fair value	53,153	42,564
Level 2 | Fair Value, Measurements, Recurring | Equity contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Level 2 | Fair Value, Measurements, Recurring | Commodity contracts
Derivative
Derivative assets - Fair value	76,615	79,604
Derivative liabilities - Fair value	106,930	121,670
Level 2 | Fair Value, Measurements, Recurring | Credit contracts
Derivative
Derivative assets - Fair value		1
Derivative liabilities - Fair value	16	25
Level 2 | Fair Value, Measurements, Recurring | U.S. Treasury securities
Available-for-sale debt securities
Fair Value	0	0
Level 2 | Fair Value, Measurements, Recurring | U.S. government agency and U.S. government-sponsored enterprise debt securities
Available-for-sale debt securities
Fair Value	360,802	364,446
Level 2 | 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	455,619	468,259
Level 2 | 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	4,992,399	1,727,594
Level 2 | Fair Value, Measurements, Recurring | Municipal securities
Available-for-sale debt securities
Fair Value	258,495	261,016
Level 2 | Fair Value, Measurements, Recurring | Non-agency commercial mortgage-backed securities
Available-for-sale debt securities
Fair Value	333,996	367,516
Level 2 | Fair Value, Measurements, Recurring | Non-agency residential mortgage-backed securities
Available-for-sale debt securities
Fair Value	519,657	553,671
Level 2 | Fair Value, Measurements, Recurring | Corporate debt securities
Available-for-sale debt securities
Fair Value	502,647	502,425
Level 2 | Fair Value, Measurements, Recurring | Foreign government bonds
Available-for-sale debt securities
Fair Value	227,196	227,874
Level 2 | Fair Value, Measurements, Recurring | Asset-backed securities
Available-for-sale debt securities
Fair Value	40,712	42,300
Level 2 | Fair Value, Measurements, Recurring | Collateralized loan obligations (“CLOs”)
Available-for-sale debt securities
Fair Value	87,851	612,861
Level 3 | Fair Value, Measurements, Recurring
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
Derivative
Derivative assets - Fair value	330	336
Netting adjustments	0	0
Net derivative assets	330	336
Derivative liabilities - Fair value	15,119	15,119
Netting adjustments	0	0
Net derivative liabilities	15,119	15,119
Level 3 | Fair Value, Measurements, Recurring | Interest rate contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Level 3 | Fair Value, Measurements, Recurring | Foreign exchange contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Level 3 | Fair Value, Measurements, Recurring | Equity contracts
Derivative
Derivative assets - Fair value	330	336
Derivative liabilities - Fair value	15,119	15,119
Level 3 | Fair Value, Measurements, Recurring | Commodity contracts
Derivative
Derivative assets - Fair value	0	0
Derivative liabilities - Fair value	0	0
Level 3 | Fair Value, Measurements, Recurring | Credit contracts
Derivative
Derivative assets - Fair value		0
Derivative liabilities - Fair value	0	0
Level 3 | Fair Value, Measurements, Recurring | U.S. Treasury securities
Available-for-sale debt securities
Fair Value	0	0
Level 3 | Fair Value, Measurements, Recurring | U.S. government agency and U.S. government-sponsored enterprise debt securities
Available-for-sale debt securities
Fair Value	0	0
Level 3 | 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	0	0
Level 3 | 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	0	0
Level 3 | Fair Value, Measurements, Recurring | Municipal securities
Available-for-sale debt securities
Fair Value	0	0
Level 3 | Fair Value, Measurements, Recurring | Non-agency commercial mortgage-backed securities
Available-for-sale debt securities
Fair Value	0	0
Level 3 | Fair Value, Measurements, Recurring | Non-agency residential mortgage-backed securities
Available-for-sale debt securities
Fair Value	0	0
Level 3 | Fair Value, Measurements, Recurring | Corporate debt securities
Available-for-sale debt securities
Fair Value	0	0
Level 3 | Fair Value, Measurements, Recurring | Foreign government bonds
Available-for-sale debt securities
Fair Value	0	0
Level 3 | Fair Value, Measurements, Recurring | Asset-backed securities
Available-for-sale debt securities
Fair Value	0	0
Level 3 | Fair Value, Measurements, Recurring | Collateralized loan obligations (“CLOs”)
Available-for-sale debt securities
Fair Value	$ 0	$ 0