Commitments and Contingencies, Contractual Commitments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Agency Business Commitments
Cash collateral	$ 131,659	$ 139,398
Debt Obligations
Remainder of 2018	477,800
2019	554,700
2020	925,700
2021	387,900
2022	71,000
Thereafter	314,700
Unfunded CLO Commitments
Unfunded commitments related to structured loans and investments	66,900
Cash collateral arrangement - purchase and loss obligations under Freddie Mac's SBL Program
Agency Business Commitments
Cash collateral per securitization	5,000
Outstanding letters of credit	$ 5,000
Forward Contracts
Agency Business Commitments
Period of contractual commitment	60 days
Fannie Mae
Agency Business Commitments
Minimum liquid assets to be maintained to meet operational liquidity requirements	$ 12,600
Period of funding for collateral requirement	48 months
Fannie Mae \| Restricted liquidity arrangement - loans sold under the Fannie Mae DUS program
Agency Business Commitments
Letter of credit assigned	$ 42,000
Cash collateral	400
Reserve required to fund additional restricted liquidity over the next 48 months	$ 28,400
Period of additional funding for collateral requirement	48 months

The additional reserve required to fund the restricted liquidity requirement.

No definition available.

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- Definition

Funding period for the additional reserve required to fund the restricted liquidity requirement.

+ References

No definition available.

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No definition available.

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- Definition

Required amount of cash collateral held for each securitization.

+ References

No definition available.

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- Definition

The amount of letter of credit assigned to meet the restricted liquidity requirement.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of outstanding unfunded commitments related to loans and investments that the entity is obligated to fund as the borrowers meet certain requirements.

+ References

No definition available.

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- Definition

The minimum liquid assets required to be maintained by the entity to meet operational liquidity requirements as of the balance sheet date.

+ References

No definition available.

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- Definition

The period over which the collateral requirement for loans will be funded.

+ References

No definition available.

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No definition available.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- References

No definition available.

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (SX 210.12-04.(a))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Period covered by the long-term purchase commitment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(1)(a))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=98513485&loc=SL98516268-108586

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3044-108585

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