Financing Arrangements, Residential Mortgage Loans (Details) - Deutsche Bank AG, Cayman Islands Branch - USD ($)	3 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Pool of Distressed Residential Mortgage Loans
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Maximum repurchase amount	$ 100,000,000
Principal amount	150,000,000
Repurchase agreement, amount outstanding	$ 119,300,000	$ 123,600,000
Repurchase agreement, effective interest rate	4.37%	4.05%
Pool of Distressed Residential Mortgage Loans \| LIBOR
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Interest rate, basis spread	2.50%
Residential Mortgage
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Maximum repurchase amount	$ 25,000,000
Principal amount	25,000,000	$ 26,100,000
Repurchase agreement, amount outstanding	$ 30,200,000
Residential Mortgage \| LIBOR
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Interest rate, basis spread	3.50%
Repurchase agreement, effective interest rate	5.12%	5.05%

The total amount of repossession that is available under the repurchase agreement.

No definition available.

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- Definition

Assets Sold Under Agreements to Repurchase, Maximum Uncommitted Repurchase Amount

+ References

No definition available.

+ Details

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- Definition

Interest rate on the amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(m)(1)(i)(A)(ii))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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- Definition

Amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets.

+ References

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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