Repurchase Agreements - Repurchase Agreements by Maturity Period (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2022	Dec. 31, 2021
Assets Sold under Agreements to Repurchase [Line Items]
Haircut percentage	3.01%	3.45%
Balance	$ 6,692,547	$ 3,948,037
Weighted Average Contractual Rate	1.38%	0.12%
Weighted Average Maturity in days	21 days	29 days
Agency Securities
Assets Sold under Agreements to Repurchase [Line Items]
Balance	$ 6,197,460	$ 3,849,037
Weighted Average Contractual Rate	1.37%	0.13%
Weighted Average Maturity in days	22 days	29 days
Agency Securities | Within 30 days
Assets Sold under Agreements to Repurchase [Line Items]
Balance	$ 4,849,273	$ 2,565,743
Weighted Average Contractual Rate	1.34%	0.13%
Weighted Average Maturity in days	16 days	13 days
Agency Securities | 31 days to 60 days
Assets Sold under Agreements to Repurchase [Line Items]
Balance		$ 647,584
Weighted Average Contractual Rate		0.13%
Weighted Average Maturity in days		35 days
Agency Securities | 31 days to 90 days
Assets Sold under Agreements to Repurchase [Line Items]
Balance	$ 1,321,582
Weighted Average Contractual Rate	1.49%
Weighted Average Maturity in days	43 days
Agency Securities | Maturity 61 To 90 Days
Assets Sold under Agreements to Repurchase [Line Items]
Balance	$ 26,605	$ 635,710
Weighted Average Contractual Rate	0.98%	0.11%
Weighted Average Maturity in days	84 days	89 days
U.S. Treasury Securities | Within 30 days
Assets Sold under Agreements to Repurchase [Line Items]
Balance	$ 495,087	$ 99,000
Weighted Average Contractual Rate	1.54%	0.12%
Weighted Average Maturity in days	1 day	3 days