Investments HTM Securities by Major Security Type (Details) - USD ($) $ in Thousands		Jun. 30, 2024	Dec. 31, 2023
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss, Total	[1]	$ 16,068,845	$ 16,832,133
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, after Allowance for Credit Loss	[2]	16,068,845	16,832,133
Held-to-maturity Securities, Unrecognized Holding Gain		7,065	25,283
Held-to-maturity Securities, Unrecognized Holding Loss		(290,576)	(280,803)
Debt Securities, Held-to-maturity, Fair Value		15,785,334	16,576,613
Debt Securities, Held-to-Maturity, Accrued Interest, after Allowance for Credit Loss		$ 63,172	$ 68,866
Debt Securities, Held-to-Maturity, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]		Accrued interest receivable	Accrued interest receivable
US Treasury Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss, Total	[1]	$ 48,637	$ 49,078
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, after Allowance for Credit Loss		48,637	49,078
Held-to-maturity Securities, Unrecognized Holding Gain		0	0
Held-to-maturity Securities, Unrecognized Holding Loss		(14)	(6)
Debt Securities, Held-to-maturity, Fair Value		48,623	49,072
Other Than Mortgage Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss, Total	[1]	48,637	49,078
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, after Allowance for Credit Loss		48,637	49,078
Held-to-maturity Securities, Unrecognized Holding Gain		0	0
Held-to-maturity Securities, Unrecognized Holding Loss		(14)	(6)
Debt Securities, Held-to-maturity, Fair Value		48,623	49,072
Single Family, Mortgage-backed Securities, Other US Obligations [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss, Total	[1]	1,055,752	1,109,265
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, after Allowance for Credit Loss		1,055,752	1,109,265
Held-to-maturity Securities, Unrecognized Holding Gain		0	0
Held-to-maturity Securities, Unrecognized Holding Loss		(150,192)	(129,457)
Debt Securities, Held-to-maturity, Fair Value		905,560	979,808
Collateralized Mortgage Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss, Total	[1]	16,020,208	16,783,055
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, after Allowance for Credit Loss		16,020,208	16,783,055
Held-to-maturity Securities, Unrecognized Holding Gain		7,065	25,283
Held-to-maturity Securities, Unrecognized Holding Loss		(290,562)	(280,797)
Debt Securities, Held-to-maturity, Fair Value		15,736,711	16,527,541
Single Family [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss, Total	[1]	3,320,308	3,146,571
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, after Allowance for Credit Loss		3,320,308	3,146,571
Held-to-maturity Securities, Unrecognized Holding Gain		4,568	23,124
Held-to-maturity Securities, Unrecognized Holding Loss		(96,967)	(79,336)
Debt Securities, Held-to-maturity, Fair Value		3,227,909	3,090,359
Multifamily [Member] | Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss, Total	[1]	11,644,148	12,527,219
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, after Allowance for Credit Loss		11,644,148	12,527,219
Held-to-maturity Securities, Unrecognized Holding Gain		2,497	2,159
Held-to-maturity Securities, Unrecognized Holding Loss		(43,403)	(72,004)
Debt Securities, Held-to-maturity, Fair Value		$ 11,603,242	$ 12,457,374

[1] Carrying value equals amortized cost. Amortized cost of held-to-maturity securities includes adjustments made to the cost basis of an investment for accretion and amortization and excludes accrued interest receivable of (in thousands) $63,172 and $68,866 at June 30, 2024 and December 31, 2023, respectively.

[2] Carrying value equals amortized cost.