Leverage ratio.

No definition available.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ 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(a)(1))
-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 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ 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

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

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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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Period Type:	instant

- Details

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- Details

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- Details

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- Details

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Unsecured Credit Agreements - Summary of Unsecured Credit Agreements (Parenthetical) (Detail) - Unsecured Debt - USD ($)	Jun. 30, 2017	Dec. 31, 2016
1 Month LIBOR
Debt Instrument [Line Items]
Interest rate	1.06%	0.62%
3 Month LIBOR
Debt Instrument [Line Items]
Interest rate		0.93%
2012 Unsecured Credit Agreement \| Revolver
Debt Instrument [Line Items]
Revolving credit facility, available borrowing capacity		$ 273,200,000
Line of credit, maximum borrowing capacity		$ 300,000,000
2013 Unsecured Credit Agreement
Debt Instrument [Line Items]
Leverage ratio		1.75%