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.

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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/disclosureRef
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- Definition

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

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

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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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- 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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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- 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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- 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/disclosureRef
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- 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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- Details

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- Details

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Long-term Debt (Details)		9 Months Ended
Long-term Debt (Details)	Sep. 13, 2016 USD ($)	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)	Oct. 26, 2017 USD ($)
Long-term debt
Net unamortized debt issuance costs		$ (8,146,000)	$ (9,000,000)
Long-term debt, net		1,516,854,000	1,196,000,000
Revolving credit facility
Long-term debt
Long-term debt		$ 875,000,000	$ 555,000,000
Maximum borrowing capacity				$ 1,500,000,000
Weighted average interest rate (as a percent)		3.39%	2.81%
Revolving credit facility \| 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%
Revolving credit facility \| 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%
Revolving credit facility \| Investment Grade Period \| Minimum
Long-term debt
Margin rates		12.5
Revolving credit facility \| Investment Grade Period \| Maximum
Long-term debt
Margin rates		200
Revolving credit facility \| Not Investment Grade Period \| Minimum
Long-term debt
Margin rates		25
Revolving credit facility \| Not Investment Grade Period \| Maximum
Long-term debt
Margin rates		225
Letter of credit
Long-term debt
Outstanding letters of credit		$ 0	$ 0
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%