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

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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Period Type:	instant

- 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

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Debt - Schedule of Credit Agreement Terms (Details) - USD ($)	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Debt Instrument [Line Items]
Revolving credit facility borrowings	$ 0	$ 160,000,000
LCIF [Member]
Debt Instrument [Line Items]
Weighted average interest rate	4.80%	4.80%
Unsecured Term Loan [Member]
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ 1,901,000	$ 3,337,000
Unsecured Revolving Credit Facility, Expiring August 2019 [Member] \| Unsecured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	$ 505,000,000
Basis spread on variable rate	1.00%
Revolving credit facility borrowings	$ 0
Remaining borrowing capacity	505,000,000
Unsecured Revolving Credit Facility, Expiring August 2019 [Member] \| Unsecured Revolving Credit Facility [Member] \| LCIF [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	$ 505,000,000
Basis spread on variable rate	1.00%
Revolving credit facility borrowings	$ 0
Remaining borrowing capacity	$ 505,000,000
Unsecured Revolving Credit Facility, Expiring August 2019 [Member] \| Unsecured Revolving Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.85%
Unsecured Revolving Credit Facility, Expiring August 2019 [Member] \| Unsecured Revolving Credit Facility [Member] \| Minimum [Member] \| LCIF [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.85%
Unsecured Revolving Credit Facility, Expiring August 2019 [Member] \| Unsecured Revolving Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.55%
Unsecured Revolving Credit Facility, Expiring August 2019 [Member] \| Unsecured Revolving Credit Facility [Member] \| Maximum [Member] \| LCIF [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.55%
Unsecured Term Loan, Expiring August 2020 [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.90%
Unsecured Term Loan, Expiring August 2020 [Member] \| Minimum [Member] \| LCIF [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.90%
Unsecured Term Loan, Expiring August 2020 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%
Unsecured Term Loan, Expiring August 2020 [Member] \| Maximum [Member] \| LCIF [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%
Unsecured Term Loan, Expiring August 2020 [Member] \| Unsecured Term Loan [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	$ 149,000,000		$ 300,000,000
Basis spread on variable rate	1.10%
Unsecured Term Loan, Expiring August 2020 [Member] \| Unsecured Term Loan [Member] \| LCIF [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	$ 149,000,000		$ 300,000,000
Basis spread on variable rate	1.10%
Unsecured Term Loan, Expiring February 2018 [Member] \| Interest Rate Swap [Member]
Debt Instrument [Line Items]
Weighted average interest rate	1.09%
Unsecured Term Loan, Expiring February 2018 [Member] \| Interest Rate Swap [Member] \| LCIF [Member]
Debt Instrument [Line Items]
Weighted average interest rate	1.09%
Unsecured Term Loan, Expiring February 2018 [Member] \| Unsecured Term Loan [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	$ 250,000,000
Unsecured Term Loan, Expiring February 2018 [Member] \| Unsecured Term Loan [Member] \| LCIF [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	$ 250,000,000
Unsecured Term Loan, Expiring January 2021 [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.90%
Unsecured Term Loan, Expiring January 2021 [Member] \| Minimum [Member] \| LCIF [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.90%
Unsecured Term Loan, Expiring January 2021 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%
Unsecured Term Loan, Expiring January 2021 [Member] \| Maximum [Member] \| LCIF [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%
Unsecured Term Loan, Expiring January 2021 [Member] \| Unsecured Term Loan [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	$ 300,000,000
Basis spread on variable rate	1.10%
Unsecured Term Loan, Expiring January 2021 [Member] \| Unsecured Term Loan [Member] \| LCIF [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	$ 300,000,000
Basis spread on variable rate	1.10%
Unsecured Term Loan, Expiring January 2019 [Member] \| Interest Rate Swap [Member]
Debt Instrument [Line Items]
Weighted average interest rate	1.42%
Unsecured Term Loan, Expiring January 2019 [Member] \| Interest Rate Swap [Member] \| LCIF [Member]
Debt Instrument [Line Items]
Weighted average interest rate	1.42%
Unsecured Term Loan, Expiring January 2019 [Member] \| Unsecured Term Loan [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	$ 255,000,000
Unsecured Term Loan, Expiring January 2019 [Member] \| Unsecured Term Loan [Member] \| LCIF [Member]
Debt Instrument [Line Items]
Face amount of debt instrument	$ 255,000,000