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

No definition available.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer upon a change of control.

+ References

No definition available.

+ Details

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer with payment of a “make-whole” premium and accrued and unpaid interest.

+ References

No definition available.

+ 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 during the investment grade period.

+ References

No definition available.

+ Details

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- Definition

Represents the percent of aggregate principal amount of notes that may be redeemed.

+ References

No definition available.

+ Details

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ 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))
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

- 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
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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Balance Type:	credit
Period Type:	instant

- 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.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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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- 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 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
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-SubTopic 210
-Section S99
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Period Type:	instant

- Definition

Weighted average interest rate of long-term debt outstanding calculated at point in time.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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Name:	us-gaap_CreditFacilityAxis=us-gaap_SeniorNotesMember
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Long-term Debt (Details)		9 Months Ended
Long-term Debt (Details)	Sep. 13, 2016 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)
Long-term debt
Net unamortized debt issuance costs		$ (9,278,000)	$ (10,086,000)
Long-term debt, net		$ 1,067,722,000	849,914,000
Margin rates		25.00
Revolving credit facility
Long-term debt
Long-term debt		$ 427,000,000	$ 210,000,000
Maximum borrowing capacity		$ 1,500,000
Weighted average interest rate (as a percent)		2.82%	2.23%
Letter of credit
Long-term debt
Maximum borrowing capacity		$ 150,000,000
Outstanding letters of credit		$ 0	$ 0
Letter of credit \| Minimum
Long-term debt
Commitment fees on the unused portion (as a percent)		0.25%
Commitment fees on the unused portion during investment grade period (as a percent)		0.175%
Letter of credit \| Maximum
Long-term debt
Commitment fees on the unused portion (as a percent)		0.375%
Commitment fees on the unused portion during investment grade period (as a percent)		0.375%
5.375% Senior Notes due 2024
Long-term debt
Long-term debt		$ 650,000,000	$ 650,000,000
Face amount	$ 650,000,000
Interest rate (as a percent)	5.375%
Debt instrument redemption percentage upon change of control	101.00%
5.375% Senior Notes due 2024 \| Maximum
Long-term debt
Percent of aggregate principal amount that can be redeemed	35.00%
5.375% Senior Notes due 2024 \| Prior to September 15, 2019
Long-term debt
Debt instrument redemption percentage	105.375%
Debt instrument redemption percentage with payment of premium and interest	100.00%
5.375% Senior Notes due 2024 \| On or after September 15, 2019
Long-term debt
Debt instrument redemption percentage	104.031%
5.375% Senior Notes due 2024 \| On or after September 15, 2022
Long-term debt
Debt instrument redemption percentage	100.00%