Securities - Summary of Portfolio of Securities Available for Sale (Details) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2022		Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Fair Value		$ 5,664		$ 5,780
Equity Securities, Fair Value		14		16
Total Securities, Amortized Cost		6,275	[1]	5,850	[2]
Total Securities, Gross Unrealized Gain		11	[1]	62	[2]
Total Securities, Gross Unrealized Loss		608	[1]	116	[2]
Total Securities, Fair Value		5,678	[1]	5,796	[2]
Mortgage-Related Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		2,772		2,819
Gross Unrealized Gain		1		31
Gross Unrealized Loss		307		60
Fair Value		2,466		2,790
Mortgage-Related Securities | GSE Certificates
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		1,161		1,102
Gross Unrealized Gain		1		20
Gross Unrealized Loss		112		15
Fair Value		1,050		1,107
Mortgage-Related Securities | GSE CMOs
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		1,611		1,717
Gross Unrealized Gain				11
Gross Unrealized Loss		195		45
Fair Value		1,416		1,683
Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		3,488		3,015
Gross Unrealized Gain		10		31
Gross Unrealized Loss		300		56
Fair Value		3,198		2,990
Debt Securities | U.S. Treasury Obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		295		45
Gross Unrealized Loss		1
Fair Value		294		45
Debt Securities | GSE Debentures
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		1,750		1,524
Gross Unrealized Gain				1
Gross Unrealized Loss		248		45
Fair Value		1,502		1,480
Debt Securities | Asset-backed Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		422	[3]	479	[4]
Gross Unrealized Gain	[4]			3
Gross Unrealized Loss		15	[3]	3	[4]
Fair Value		407	[3]	479	[4]
Debt Securities | Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		881		821
Gross Unrealized Gain		4		18
Gross Unrealized Loss		26		1
Fair Value		859		838
Debt Securities | Municipal Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		19		25
Gross Unrealized Loss		1
Fair Value		18		25
Debt Securities | Foreign Notes
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		25		25
Gross Unrealized Gain				1
Fair Value		25		26
Debt Securities | Capital Trust Notes
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		96		96
Gross Unrealized Gain		6		8
Gross Unrealized Loss		9		7
Fair Value		93		97
Mortgage Backed Securities And Other Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		6,260		5,834
Gross Unrealized Gain		11		62
Gross Unrealized Loss		607		116
Fair Value		5,664		5,780
Equity Securities
Schedule of Available-for-sale Securities [Line Items]
Equity Securities, Amortized Cost		15		16
Equity Securities, Gross Unrealized Loss		1
Equity Securities, Fair Value		14		16
Equity Securities | Mutual Funds
Schedule of Available-for-sale Securities [Line Items]
Equity Securities, Amortized Cost		15		16
Equity Securities, Gross Unrealized Loss		1
Equity Securities, Fair Value		$ 14		$ 16

[1] Excludes accrued interest receivable of $18 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.