Fair Value of Financial Instruments Recorded basis and Fair Value (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative assets	$ 5,237	$ 18,488
Derivative Liabilities, Fair Value Disclosure	23,974	6,681
Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage-backed securities, Fair Value Disclosure	3,949,965	4,018,161
Mortgage loans held for investment, net, Fair Value Disclosure	52,564	55,423
Derivative assets	5,237	18,488
Repurchase Agreements, Fair Value Disclosure	3,447,050	3,580,754
Non-recourse collateralized financing, Fair Value Disclosure	12,073	12,914
Derivative Liabilities, Fair Value Disclosure	23,974	6,681
Estimate of Fair Value, Fair Value Disclosure [Member] \| Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mortgage-backed securities, Fair Value Disclosure	3,949,965	4,018,161
Mortgage loans held for investment, net, Fair Value Disclosure	44,252	46,383
Derivative assets	5,237	18,488
Repurchase Agreements, Fair Value Disclosure	3,447,085	3,580,997
Non-recourse collateralized financing, Fair Value Disclosure	11,603	12,414
Derivative Liabilities, Fair Value Disclosure	$ 23,974	$ 6,681

Fair value portion of investments accounted under the cost method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 325

-SubTopic 20

-Section 25

-Paragraph 1

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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No definition available.

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- Definition

Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Mortgage-Backed Securities

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- Definition

Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

+ References

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