Financing Agreements (Borrowings Under Repurchase Agreement And Associated Assets Pledged as Collateral) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Assets Sold under Agreements to Repurchase [Line Items]
Fair value of securities pledged as collateral under repurchase agreements	$ 5,700,000	$ 11,300,000
Agreements with mark-to-market collateral provisions
Assets Sold under Agreements to Repurchase [Line Items]
Carrying Value		0
Fair value of securities pledged as collateral under repurchase agreements	$ 2,668,741	$ 0
Weighted average haircut (percent)	34.29%	0.00%
Financing agreements	$ 1,778,845
Agreements with non-mark-to-market collateral provisions
Assets Sold under Agreements to Repurchase [Line Items]
Carrying Value		$ 0
Fair value of securities pledged as collateral under repurchase agreements	$ 425,673	$ 0
Weighted average haircut (percent)	32.80%	0.00%
Financing agreements	$ 257,752
Residential whole loans
Assets Sold under Agreements to Repurchase [Line Items]
Carrying Value	1,386,592	$ 4,743,094
Fair value of securities pledged as collateral under repurchase agreements	$ 2,166,740	$ 5,986,267
Weighted average haircut (percent)	33.81%	20.07%
Agency MBS
Assets Sold under Agreements to Repurchase [Line Items]
Carrying Value	$ 0	$ 1,557,675
Fair value of securities pledged as collateral under repurchase agreements	$ 0	$ 1,656,373
Weighted average haircut (percent)	0.00%	4.46%
Non-Agency MBS
Assets Sold under Agreements to Repurchase [Line Items]
Carrying Value	$ 1,282	$ 1,121,802
Fair value of securities pledged as collateral under repurchase agreements	$ 2,564	$ 1,420,797
Weighted average haircut (percent)	50.00%	20.27%
RPL/NPL MBS
Assets Sold under Agreements to Repurchase [Line Items]
Carrying Value	$ 29,785	$ 495,091
Fair value of securities pledged as collateral under repurchase agreements	$ 51,540	$ 635,005
Weighted average haircut (percent)	38.10%	21.52%
CRT securities
Assets Sold under Agreements to Repurchase [Line Items]
Carrying Value	$ 54,469	$ 203,569
Fair value of securities pledged as collateral under repurchase agreements	$ 94,106	$ 252,175
Weighted average haircut (percent)	42.40%	18.84%
MSR-related assets
Assets Sold under Agreements to Repurchase [Line Items]
Carrying Value	$ 146,642	$ 962,515
Fair value of securities pledged as collateral under repurchase agreements	$ 255,035	$ 1,217,002
Weighted average haircut (percent)	38.24%	21.18%
Other Interest Earning Assets
Assets Sold under Agreements to Repurchase [Line Items]
Carrying Value	$ 37,478	$ 57,198
Fair value of securities pledged as collateral under repurchase agreements	$ 48,471	$ 61,708
Weighted average haircut (percent)	20.00%	22.01%
Repurchase Agreement Borrowings
Assets Sold under Agreements to Repurchase [Line Items]
Financing agreements	$ 3,692,845	$ 9,140,944
Unamortized debt issuance expense	0	1,123
Loan Securitization
Assets Sold under Agreements to Repurchase [Line Items]
Fair value of securities pledged as collateral under repurchase agreements	179,100	238,800
MSR Asset Financing
Assets Sold under Agreements to Repurchase [Line Items]
Cash pledged as collateral	$ 7,700	$ 25,200

Financing Agreements, Liabilities

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- Definition

The weighted average percentage amount by which the collateral value is contractually required to exceed the loan amount on the Company's repurchase agreements borrowings.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The fair value, as of the date of each statement of financial position presented, of securities which are owned but transferred to serve as collateral for the payment of repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

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- Definition

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against securities sold under agreement to repurchase.

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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