Securities - Summary of Portfolio of Securities Available for Sale (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2022		Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Fair value		$ 9,060		$ 5,780
Equity Securities, Fair Value		14		16
Total Securities, Amortized Cost		9,933	[1]	5,850	[2]
Total Securities, Gross Unrealized Gain		14	[1]	62	[2]
Total Securities, Gross Unrealized Loss		873	[1]	116	[2]
Total Securities, Fair Value		9,074	[1]	5,796	[2]
Mortgage-Related Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		5,242		2,819
Gross Unrealized Gain		7		31
Gross Unrealized Loss		460		60
Fair value		4,789		2,790
Mortgage-Related Securities | GSE Certificates
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		1,457		1,102
Gross Unrealized Gain				20
Gross Unrealized Loss		160		15
Fair value		1,297		1,107
Mortgage-Related Securities | GSE CMOs
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		3,600		1,717
Gross Unrealized Gain		1		11
Gross Unrealized Loss		300		45
Fair value		3,301		1,683
Mortgage-Related Securities | Private Label CMOs
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		185
Gross Unrealized Gain		6
Fair value		191
Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		4,675		3,015
Gross Unrealized Gain		7		31
Gross Unrealized Loss		411		56
Fair value		4,271		2,990
Debt Securities | U.S. Treasury Obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		1,491		45
Gross Unrealized Loss		4
Fair value		1,487		45
Debt Securities | GSE Debentures
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		1,749		1,524
Gross Unrealized Gain				1
Gross Unrealized Loss		351		45
Fair value		1,398		1,480
Debt Securities | Asset-backed Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		375	[3]	479	[4]
Gross Unrealized Gain	[4]			3
Gross Unrealized Loss		14	[3]	3	[4]
Fair value		361	[3]	479	[4]
Debt Securities | Municipal Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		30		25
Fair value		30		25
Debt Securities | Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		913		821
Gross Unrealized Gain		2		18
Gross Unrealized Loss		30		1
Fair value		885		838
Debt Securities | Foreign Notes
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		20		25
Gross Unrealized Gain				1
Fair value		20		26
Debt Securities | Capital Trust Notes
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		97		96
Gross Unrealized Gain		5		8
Gross Unrealized Loss		12		7
Fair value		90		97
Mortgage Backed Securities And Other Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		9,917		5,834
Gross Unrealized Gain		14		62
Gross Unrealized Loss		871		116
Fair value		9,060		5,780
Equity Securities
Schedule of Available-for-sale Securities [Line Items]
Equity Securities, Amortized Cost		16		16
Equity Securities, Gross Unrealized Loss		2
Equity Securities, Fair Value		14		16
Equity Securities | Mutual Funds
Schedule of Available-for-sale Securities [Line Items]
Equity Securities, Amortized Cost		16		16
Equity Securities, Gross Unrealized Loss		2
Equity Securities, Fair Value		$ 14		$ 16

[1] Excludes accrued interest receivable of $31 million included in other assets in the Consolidated Statements of Condition.

[2] Excludes accrued interest receivable of $15 million included in other assets in the Consolidated Statements of Condition.

[3] The underlying assets of the asset-backed securities are substantially guaranteed by the U.S. Government.

[4] The underlying assets of the asset-backed securities are substantially guaranteed by the U.S. Government.