Residential Mortgage Securities and MSR-Related Assets (Purchase Discounts) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Discount Designated as Credit Reserve and OTTI \| Non-Agency MBS
Changes in the components of the purchase discount on Non-Agency MBS
Balance at beginning of period	$ (516,116)	$ (593,227)
Impact of RMBS Issuer Settlement	0	0
Accretion of discount	0	0
Realized credit losses	7,504	8,447
Purchases	0	(535)
Sales	3,191	5,592
Transfers/release of credit reserve	3,802	7,143
Balance at end of period	(501,619)	(572,580)
Accretable Discount \| Non-Agency MBS
Changes in the components of the purchase discount on Non-Agency MBS
Balance at beginning of period	(155,025)	(215,325)
Impact of RMBS Issuer Settlement	(855)	0
Accretion of discount	13,307	17,216
Realized credit losses	0	0
Purchases	(118)	488
Sales	16,346	5,105
Transfers/release of credit reserve	(3,802)	(7,143)
Balance at end of period	(130,147)	$ (199,659)
Jp Morgan Chase
Changes in the components of the purchase discount on Non-Agency MBS
Proceeds from legal settlements	$ 855

Represents the changes in the purchase discount on available-for-sale securities due to purchases during the period.

No definition available.

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- Definition

Represents the changes in the purchase discount on available-for-sale securities due to sales during the period.

+ References

No definition available.

+ Details

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- Definition

Available For Sale Securities, Changes in Purchase Discount Due to Settlements

+ References

No definition available.

+ Details

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- Definition

Represent the total amount of purchase discount related to available-for-sale securities.

+ References

No definition available.

+ Details

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- Definition

Represent the amount of purchase discount on available-for-sale securities designated as credit reserves reallocated during the period to accretable purchase discount.

+ References

No definition available.

+ Details

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- Definition

-- None. No documentation exists for this element. --

+ References

No definition available.

+ Details

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- Definition

Amount of accretion of purchase discount on nonoperating securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

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- Definition

Amount of tax (expense) benefit of other than temporary impairment (OTTI) on investment in available-for-sale debt security, recognized in other comprehensive loss.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 35
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=115930623&loc=d3e25362-111560

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Cash received for the settlement of litigation during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3536-108585

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