Debt instrument extension period.

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- Definition

Debt Instrument, Number of Extensions Available

+ References

No definition available.

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- Definition

Line of Credit, Covenant, Minimum Shareholder's Equity of Gross Capital Proceeds

+ References

No definition available.

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- Definition

Line of Credit Facility, Period of Potential Extension

+ References

No definition available.

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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

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

Reference 3: 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(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Balance Type:	credit
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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

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

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

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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-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
-Topic 210
-SubTopic 20
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=49176635&loc=d3e9760-107771

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Borrowings Under Repurchase Agreements - Additional Information (Detail) £ in Thousands				1 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2017 USD ($) subsidiary	Sep. 29, 2016 USD ($) extension	Jan. 26, 2015	Apr. 30, 2014 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2017 GBP (£)	Sep. 29, 2016 GBP (£)	Sep. 30, 2013 USD ($)
Debt Instrument [Line Items]
Borrowing outstanding					$ 1,278,631,000	$ 1,139,803,000
Line of Credit [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility					2,017,671,000
Borrowing outstanding					$ 1,278,631,000	$ 1,139,803,000
Line of Credit [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread					1.23%	0.77%
Line of Credit [Member] \| JPMorgan Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility					$ 1,118,000,000	$ 943,000,000
Borrowing outstanding					840,360,000	657,452,000
Line of Credit [Member] \| DB Repurchase Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility		$ 565,491,000			565,491,000	300,000,000
Borrowing outstanding					265,658,000	137,355,000
Number of extensions available \| extension		2
Line of credit facility, potential extension period		1 year
Line of Credit [Member] \| Goldman Loan [Member]
Debt Instrument [Line Items]
Borrowing outstanding					34,180,000	40,657,000
Line of Credit [Member] \| UBS Facility [Member]
Debt Instrument [Line Items]
Borrowing outstanding						133,899,000
Line of Credit [Member] \| DB Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility					300,000,000
Borrowing outstanding					$ 149,317,000	$ 177,203,000
Minimum [Member] \| Line of Credit [Member] \| DB Repurchase Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread					2.10%
Minimum [Member] \| Line of Credit [Member] \| DB Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread					2.09%
Maximum [Member] \| Line of Credit [Member] \| DB Repurchase Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread					3.00%
Maximum [Member] \| Line of Credit [Member] \| DB Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread					2.39%
JP Morgan Facility [Member] \| Line of Credit [Member] \| JPMorgan Facility [Member]
Debt Instrument [Line Items]
Number of indirect wholly owned subsidiaries \| subsidiary	2
Amended and Restated JPMorgan Facility [Member] \| Line of Credit [Member] \| JPMorgan Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility	$ 1,118,000,000
Debt extension option	1 year
Threshold amount for margin calls (more than)	$ 250,000
Amended and Restated JPMorgan Facility [Member] \| Minimum [Member] \| Line of Credit [Member] \| JPMorgan Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread	2.25%
Amended and Restated JPMorgan Facility [Member] \| Maximum [Member] \| Line of Credit [Member] \| JPMorgan Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread	3.50%
Repurchase Facility [Member] \| Line of Credit [Member] \| JPMorgan Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility	$ 975,000,000
Asset Specific Financing [Member] \| Line of Credit [Member] \| JPMorgan Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility	$ 143,000,000
Long-term line of credit					$ 143,000,000
Asset Specific Financing [Member] \| Line of Credit [Member] \| DB Repurchase Facility [Member]
Debt Instrument [Line Items]
Long-term line of credit		$ 55,200,000			55,200,000
General Facility [Member] \| Line of Credit [Member] \| JPMorgan Facility [Member]
Debt Instrument [Line Items]
Long-term line of credit					975,000,000
General Facility [Member] \| Line of Credit [Member] \| DB Repurchase Facility [Member]
Debt Instrument [Line Items]
Long-term line of credit		$ 450,000,000			450,000,000		£ 45,000	£ 45,000
Goldman Facility [Member] \| Line of Credit [Member] \| Goldman Loan [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility					$ 34,180,000
Goldman Facility [Member] \| Line of Credit [Member] \| Goldman Loan [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread			3.50%
UBS Facility [Member] \| Line of Credit [Member] \| UBS Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility									$ 133,899
DB Facility [Member] \| Line of Credit [Member] \| DB Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing under facility				$ 300,000,000
Line of credit, covenant, minimum shareholder's equity of gross capital Proceeds				50.00%
DB Facility [Member] \| Minimum [Member] \| Line of Credit [Member] \| DB Facility [Member] \| Three Month LIBOR [Member]
Debt Instrument [Line Items]
Basis spread					2.09%
DB Facility [Member] \| Maximum [Member] \| Line of Credit [Member] \| DB Facility [Member] \| Three Month LIBOR [Member]
Debt Instrument [Line Items]
Basis spread					2.39%
Line of credit facility, non-use commitment fee percentage				1.80%