Debt instrument extension period.

No definition available.

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- Definition

Debt Instrument, Number of Extensions Available

+ References

No definition available.

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- Definition

Line of Credit Facility, Period of Potential Extension

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Threshold Amount for Margin Calls

+ References

No definition available.

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- Definition

Number of Subsidiaries, Covenant Terms

+ References

No definition available.

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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.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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- Definition

Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities 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 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
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Secured Debt Arrangements, Net - Additional Information (Details) £ in Thousands		1 Months Ended	3 Months Ended								12 Months Ended
	Mar. 31, 2017 USD ($) extension subsidiary	Oct. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2017 GBP (£)	Mar. 31, 2017 GBP (£)	Apr. 30, 2014 USD ($)	Sep. 30, 2013 USD ($)
Debt Instrument [Line Items]
Borrowings outstanding			$ 1,330,847,000				$ 1,139,803,000				$ 1,330,847,000	$ 1,139,803,000
Loss on early debt extinguishment			1,947,000	$ 0	$ 0	$ 0	0	$ 0	$ 0	$ 0	1,947,000	0	$ 0
Line of Credit [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility			2,290,139,000								2,290,139,000
Borrowings outstanding			1,330,847,000				1,139,803,000				$ 1,330,847,000	$ 1,139,803,000
Line of Credit [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate											1.564%	0.77%
Line of Credit [Member] \| JP Morgan Chase [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility			1,393,000,000				943,000,000				$ 1,393,000,000	$ 943,000,000
Borrowings outstanding			944,529,000				657,452,000				$ 944,529,000	$ 657,452,000
Line of Credit [Member] \| JP Morgan Chase [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate											2.30%	2.25%
Line of Credit [Member] \| Deutsche Bank Repurchase Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility	$ 566,009,000		566,009,000			566,009,000	300,000,000				$ 566,009,000	$ 300,000,000
Borrowings outstanding			319,286,000				137,355,000				$ 319,286,000	$ 137,355,000		£ 69,503
Debt instrument, number of extension available \| extension	2
Length of potential extension	1 year
Line of Credit [Member] \| Deutsche Bank Repurchase Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate											2.27%	2.66%
Line of Credit [Member] \| Goldman Sachs Repurchase Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility			331,130,000								$ 331,130,000
Borrowings outstanding			81,380,000				40,657,000				$ 81,380,000	$ 40,657,000
Line of Credit [Member] \| Goldman Sachs Repurchase Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate											2.73%	3.50%
Line of Credit [Member] \| Deutsche Bank [Member]
Debt Instrument [Line Items]
Borrowings outstanding							177,203,000					$ 177,203,000
Line of Credit [Member] \| UBS [Member]
Debt Instrument [Line Items]
Borrowings outstanding							$ 133,899,000					$ 133,899,000
Line of Credit [Member] \| Minimum [Member] \| Deutsche Bank Repurchase Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate											2.10%
Line of Credit [Member] \| Maximum [Member] \| Deutsche Bank Repurchase Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate											3.00%
JP Morgan Facility [Member] \| Line of Credit [Member] \| JP Morgan Chase [Member]
Debt Instrument [Line Items]
Number of subsidiaries \| subsidiary	2
Amended and Restated JPMorgan Facility [Member] \| Line of Credit [Member] \| JP Morgan Chase [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility		$ 1,393,000
Extension option	1 year
Threshold amount for margin calls		$ 250
Amended and Restated JPMorgan Facility [Member] \| Line of Credit [Member] \| Minimum [Member] \| JP Morgan Chase [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate		2.25%
Amended and Restated JPMorgan Facility [Member] \| Line of Credit [Member] \| Maximum [Member] \| JP Morgan Chase [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate		2.75%
Repurchase Facility [Member] \| Line of Credit [Member] \| JP Morgan Chase [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility		$ 1,250,000
Asset Specific Financing [Member] \| Line of Credit [Member] \| JP Morgan Chase [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility		$ 143,000
Line of credit, amount outstanding			143,000,000								$ 143,000,000
Asset Specific Financing [Member] \| Line of Credit [Member] \| Deutsche Bank Repurchase Facility [Member]
Debt Instrument [Line Items]
Line of credit, amount outstanding	$ 55,200,000		55,200,000			55,200,000					55,200,000
Asset Specific Financing [Member] \| Line of Credit [Member] \| Goldman Sachs Repurchase Facility [Member]
Debt Instrument [Line Items]
Line of credit, amount outstanding			31,130,000								31,130,000
General Facility [Member] \| Line of Credit [Member] \| JP Morgan Chase [Member]
Debt Instrument [Line Items]
Line of credit, amount outstanding			1,250,000,000								1,250,000,000
General Facility [Member] \| Line of Credit [Member] \| Deutsche Bank Repurchase Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility	450,000,000					450,000,000									£ 24,503
Line of credit, amount outstanding	$ 170,168,000		450,000,000			$ 170,168,000					450,000,000			£ 45,000	£ 45,000
General Facility [Member] \| Line of Credit [Member] \| Goldman Sachs Repurchase Facility [Member]
Debt Instrument [Line Items]
Borrowings outstanding			50,250,000								50,250,000
Line of credit, amount outstanding			$ 300,000,000								300,000,000
DB Facility [Member] \| Line of Credit [Member] \| Deutsche Bank [Member] \| Three Month LIBOR [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility																$ 300,000,000
UBS Facility [Member] \| Line of Credit [Member] \| UBS [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility																	$ 133,899,000
Commercial Mortgage Backed Securities [Member]
Debt Instrument [Line Items]
Loss on early debt extinguishment											$ 1,947,000