Use of Special Purpose Entities and Variable Interest Entities (Details) - USD ($) $ in Thousands		1 Months Ended		3 Months Ended		6 Months Ended
		Feb. 29, 2012	Oct. 31, 2010	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Special purpose entities and variable interest entities
Outstanding amount of Senior Bonds	[1]			$ 62,320		$ 62,320		$ 110,574
Available-for-sale securities				12,342,274		12,342,274		10,762,622
Residential whole loans				429,300		429,300		351,400
Residential whole loans at carrying value				245,402		245,402		207,923
Residential whole loans, at fair value				$ 183,861		$ 183,861		143,472
Ownership percentage by parent				100.00%		100.00%
Residential whole loans held at carrying value				$ 4,193	$ 0	$ 7,784	$ 0
Net gain on residential whole loans held at fair value				3,163	$ 0	5,197	$ 0
Non-Agency MBS
Special purpose entities and variable interest entities
Available-for-sale securities				6,882,153		6,882,153		4,755,432
Non-Agency MBS | Recurring basis
Special purpose entities and variable interest entities
Available-for-sale securities				6,882,153		6,882,153
Non-Agency MBS | Level 3 | Recurring basis
Special purpose entities and variable interest entities
Available-for-sale securities				0		0
Residential whole loans | Recurring basis
Special purpose entities and variable interest entities
Residential whole loans, at fair value				183,861		183,861
Residential whole loans | Level 3 | Recurring basis
Special purpose entities and variable interest entities
Residential whole loans, at fair value				183,861		183,861
WFMLT Series 2012-RR1
Special purpose entities and variable interest entities
Principal value of Non-Agency MBS sold		$ 433,347
Face amount of Bonds issued by the VIE and purchased by 3rd party investors		186,691
Outstanding amount of Senior Bonds		$ 41,317
Pass-through rate for Senior Bonds issued		2.85%
Cash received		$ 186,691
Notional amount acquired of non-rated, interest only senior certificates		186,691
Unamortized deferred costs		356
WFMLT Series 2012-RR1 | Senior-support certificates
Special purpose entities and variable interest entities
Face amount of Senior Support Certificates received by the Company		$ 218,445
Deutsche Mortgage Securities, Inc. Real Estate Mortgage Investment Conduit Trust, Series 2010-RS2
Special purpose entities and variable interest entities
Principal value of Non-Agency MBS sold			$ 985,228
Face amount of Bonds issued by the VIE and purchased by 3rd party investors			373,577
Outstanding amount of Senior Bonds			$ 21,003
Pass-through rate for Senior Bonds issued, description			Weighted Average Coupon Rate
Cash received			$ 375,621
Notional amount acquired of non-rated, interest only senior certificates			0
Unamortized deferred costs			0
Deutsche Mortgage Securities, Inc. Real Estate Mortgage Investment Conduit Trust, Series 2010-RS2 | Senior-support certificates
Special purpose entities and variable interest entities
Face amount of Senior Support Certificates received by the Company			$ 475,177
Variable Interest Entity, Primary Beneficiary | Non-Agency MBS
Special purpose entities and variable interest entities
Available-for-sale securities	[2]			$ 659,500		$ 659,500		$ 1,397,000
Trust, ownership in residential whole loans
Special purpose entities and variable interest entities
Ownership percentage by parent				100.00%		100.00%

[1] Securitized debt represents third-party liabilities of consolidated VIEs and excludes liabilities of the VIEs acquired by the Company that eliminate on consolidation. The third-party beneficial interest holders in the VIEs have no recourse to the general credit of the Company. (See Notes 12 and 17 for further discussion.)

[2] Non-Agency MBS transferred to consolidated VIEs represent assets of the consolidated VIEs that can be used only to settle the obligations of each respective VIE.