Derivatives and Hedging Activities - Derivative Instrument Information (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2024 USD ($)
Derivatives
Notional amount, beginning balance	$ 4,065,000
Additions	3,390,000
Settlement, Termination, Expiration or Exercise	(3,175,000)
Notional amount, ending balance	4,280,000
Interest Rate Swaps
Derivatives
Notional amount, beginning balance	4,065,000
Additions	2,640,000
Settlement, Termination, Expiration or Exercise	(2,915,000)
Notional amount, ending balance	3,790,000
Futures Contracts
Derivatives
Notional amount, beginning balance	0
Additions	750,000
Settlement, Termination, Expiration or Exercise	(260,000)
Notional amount, ending balance	490,000
TBA Purchase Contracts
Derivatives
Notional amount, beginning balance	0
Additions	1,100,000
Settlement, Termination, Expiration or Exercise	(1,100,000)
Notional amount, ending balance	0
TBA Sale Contracts
Derivatives
Notional amount, beginning balance	0
Additions	(1,100,000)
Settlement, Termination, Expiration or Exercise	1,100,000
Notional amount, ending balance	$ 0