Debt instrument extension period.

No definition available.

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- Definition

Debt Instrument, Number of Extensions Available

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Period of Potential Extension

+ References

No definition available.

+ Details

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- Definition

Number of Subsidiaries, Covenant Terms

+ References

No definition available.

+ 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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- 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
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Balance Type:	credit
Period Type:	instant

- 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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Period Type:	instant

- 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)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: 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)(a)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226008-175313

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=49176635&loc=d3e9760-107771

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Secured Debt Arrangements, Net - Additional Information (Details) £ in Millions		3 Months Ended	12 Months Ended
	Mar. 31, 2017 USD ($) extension subsidiary	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Mar. 31, 2018 GBP (£)	Mar. 31, 2017 GBP (£)
Debt Instrument [Line Items]
Borrowings outstanding		$ 1,212,749,000	$ 1,330,847,000
Line of Credit [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility		2,277,906,000	2,290,139,000
Borrowings outstanding		1,212,749,000	1,330,847,000
Line of Credit [Member] \| JP Morgan Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility		1,382,000,000	1,393,000,000
Borrowings outstanding		$ 800,535,000	$ 944,529,000
Line of Credit [Member] \| JP Morgan Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate		2.30%	2.30%
Line of Credit [Member] \| DB Repurchase Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility	$ 568,200,000
Borrowings outstanding		$ 323,200,000		£ 118.3
Debt instrument, number of extension available \| extension	1
Length of potential extension	1 year
Line of Credit [Member] \| DB Repurchase Facility [Member] \| GBP London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate		2.60%
Line of Credit [Member] \| Goldman Sachs Repurchase Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility		$ 327,750,000	$ 331,130,000
Borrowings outstanding		$ 103,025,000	$ 81,380,000
Line of Credit [Member] \| Goldman Sachs Repurchase Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate		2.57%	2.73%
Line of Credit [Member] \| Minimum [Member] \| DB Repurchase Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate		2.10%
Line of Credit [Member] \| Minimum [Member] \| Goldman Sachs Repurchase Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate		2.20%
Line of Credit [Member] \| Maximum [Member] \| DB Repurchase Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate		3.00%
Line of Credit [Member] \| Maximum [Member] \| Goldman Sachs Repurchase Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread on interest rate		3.50%
JP Morgan Facility [Member] \| Line of Credit [Member] \| JP Morgan Facility [Member]
Debt Instrument [Line Items]
Number of subsidiaries \| subsidiary	2
Amended and Restated JPMorgan Facility [Member] \| Line of Credit [Member] \| JP Morgan Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility	$ 1,382,000
Extension option	1 year
Amended and Restated JPMorgan Facility [Member] \| Line of Credit [Member] \| Minimum [Member] \| JP Morgan Facility [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 Facility [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 Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility	$ 1,250,000
Asset Specific Financing [Member] \| Line of Credit [Member] \| JP Morgan Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility	132,000
Line of credit, amount outstanding		$ 132,000,000
Asset Specific Financing [Member] \| Line of Credit [Member] \| DB Repurchase Facility [Member]
Debt Instrument [Line Items]
Line of credit, amount outstanding	55,100,000	55,100,000		£ 45.0
Asset Specific Financing [Member] \| Line of Credit [Member] \| Goldman Sachs Repurchase Facility [Member]
Debt Instrument [Line Items]
Line of credit, amount outstanding		27,800,000
General Facility [Member] \| Line of Credit [Member] \| JP Morgan Facility [Member]
Debt Instrument [Line Items]
Line of credit, amount outstanding		1,300,000,000
General Facility [Member] \| Line of Credit [Member] \| DB Repurchase Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility	450,000,000				£ 73.3
Line of credit, amount outstanding	$ 102,400,000	450,000,000			£ 45.0
General Facility [Member] \| Line of Credit [Member] \| Goldman Sachs Repurchase Facility [Member]
Debt Instrument [Line Items]
Borrowings outstanding		75,200,000
Line of credit, amount outstanding		$ 300,000,000