Credit Facility, Aggregate Additional Borrowing Capacity Available

No definition available.

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- Definition

Represents the period over which the debt may be extended at the option of the entity, subject to certain conditions.

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Extension Fee Percentage

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Maturity Date Extension, Number of Extensions

+ 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.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
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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))
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ 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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Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt discount.

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-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt premium.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
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Period Type:	instant

- Definition

Amount of interest capitalized during the period.

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Balance Type:	debit
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
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-Section S99
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Period Type:	instant

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Debt, Net (Details)	3 Months Ended
Debt, Net (Details)	Mar. 31, 2018 USD ($) extension	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)
Debt
Carrying Value	$ 1,854,886,000		$ 1,828,333,000
Interest costs capitalized	1,400,000	$ 1,500,000
Secured Debt
Debt
Carrying Value	$ 162,864,000		163,838,000
Line of Credit \| Revolving Credit Facility
Debt
Number of extensions \| extension	2
Extension option period (in years)	6 months
Line of credit facility, extension fee percentage	0.075%
Loans payable
Debt
Deferred financing costs, net	$ 4,800,000		5,000,000
Fixed rate debt \| Secured Debt
Debt
Carrying Value	149,835,000		150,723,000
Unamortized premium included in carrying value	$ 332,000		349,000
Weighted average interest rate (as a percent)	4.18%
Fixed rate debt \| Secured Debt \| Minimum
Debt
Stated interest rate (as a percent)	3.82%
Fixed rate debt \| Secured Debt \| Maximum
Debt
Stated interest rate (as a percent)	7.87%
Variable-rate debt \| Secured Debt
Debt
Carrying Value	$ 13,029,000		13,115,000
Stated interest rate (as a percent)	3.51%
Variable-rate debt \| Secured Debt \| London Interbank Offered Rate (LIBOR)
Debt
Variable rate, spread (as a percent)	1.85%
Revolving Credit Facility
Debt
Carrying Value	$ 153,000,000		126,000,000
Weighted average interest rate (as a percent)	2.77%
Revolving Credit Facility \| Minimum \| London Interbank Offered Rate (LIBOR)
Debt
Variable rate, spread (as a percent)	0.875%
Revolving Credit Facility \| Maximum \| London Interbank Offered Rate (LIBOR)
Debt
Variable rate, spread (as a percent)	1.60%
Term Loan Facilities
Debt
Carrying Value	$ 348,072,000		347,959,000
Weighted average interest rate (as a percent)	3.03%
Aggregate additional borrowing capacity available	$ 350,000,000
Term Loan Facilities \| Minimum \| London Interbank Offered Rate (LIBOR)
Debt
Variable rate, spread (as a percent)	0.90%
Term Loan Facilities \| Maximum \| London Interbank Offered Rate (LIBOR)
Debt
Variable rate, spread (as a percent)	1.85%
3.60% Senior Notes \| Unsecured senior notes
Debt
Carrying Value	$ 347,659,000		347,551,000
Debt instrument, face amount	$ 350,000,000
Stated interest rate (as a percent)	3.60%
Unamortized discount included in carrying value	$ 1,600,000		1,700,000
Interest rate on debt (as a percent)	3.70%
5.250% Senior Notes \| Unsecured senior notes
Debt
Carrying Value	$ 246,765,000		246,645,000
Debt instrument, face amount	$ 250,000,000
Stated interest rate (as a percent)	5.25%
Unamortized discount included in carrying value	$ 2,900,000		3,000,000
Interest rate on debt (as a percent)	5.49%
3.70% Senior Notes \| Unsecured senior notes
Debt
Carrying Value	$ 298,444,000		298,322,000
Debt instrument, face amount	$ 300,000,000
Stated interest rate (as a percent)	3.70%
Unamortized discount included in carrying value	$ 1,200,000		1,300,000
Interest rate on debt (as a percent)	3.85%
5.000% Senior Notes \| Unsecured senior notes
Debt
Carrying Value	$ 296,824,000		296,731,000
Debt instrument, face amount	$ 300,000,000
Stated interest rate (as a percent)	5.00%
Unamortized discount included in carrying value	$ 2,600,000		2,700,000
Interest rate on debt (as a percent)	5.15%
Unsecured notes payable
Debt
Carrying Value	$ 1,258,000		1,287,000
Stated interest rate (as a percent)	0.00%
Unamortized discount included in carrying value	$ 353,000		$ 373,000