Annual Debt Amortization Rate - Term Loan Facility

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Debt Instrument, Redemption Price For Equity Offerings, Percentage

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Amount of amortization expense attributable to debt issuance costs.

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

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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.

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

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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

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

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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.

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

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Percentage of principal amount of debt redeemed.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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.

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The effective interest rate at the end of the reporting period.

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The effective interest rate during the reporting period.

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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.

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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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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Debt - Additional Information (Details)		3 Months Ended
Debt - Additional Information (Details)	Sep. 25, 2018 USD ($)	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months		$ 4,100,000
Amount borrowed		620,300,000		$ 622,100,000
Deferred debt issuance costs		6,900,000		7,200,000
Long-term Debt, Fiscal Year Maturity [Abstract]
2020		3,200,000
2021		3,800,000
2022		3,700,000
2023		78,900,000
Thereafter		541,000,000
Total		634,700,000
Interest expense
Debt Instrument [Line Items]
Amortization of debt issuance costs		300,000	$ 500,000
Senior unsecured notes
Long-term Debt, Fiscal Year Maturity [Abstract]
Fair market value		$ 354,400,000		331,600,000
New Credit Facility
Debt Instrument [Line Items]
Maximum borrowings under credit facility	$ 700,000,000.0
EBITDA ratio	4.50
Interest coverage ratio	3.00
Effective interest rate on debt facilities		4.42%	3.44%
6.875% Senior Unsecured Notes Due 2026 \| Senior unsecured notes
Debt Instrument [Line Items]
Debt instrument, face amount	$ 350,000,000.0
Interest rate	6.875%
Effective rate		7.248%
Redemption price, percentage	100.00%
Amount to be redeemed, percentage	35.00%
Redemption price for equity offerings, percentage	106.875%
Long-term Debt, Fiscal Year Maturity [Abstract]
Total		$ 342,500,000		342,400,000
Revolving credit facility - U.S. dollar borrowings \| Revolving credit facility
Long-term Debt, Fiscal Year Maturity [Abstract]
Total		$ 76,000,000		76,000,000
Term loan facility \| Term loan facility
Debt Instrument [Line Items]
Debt instrument term	7 years
Debt instrument, face amount	$ 200,000,000.0
Amortization rate		1.00%
Average interest rate on outstanding borrowings		4.25%
Long-term Debt, Fiscal Year Maturity [Abstract]
Total		$ 199,000,000		$ 199,500,000
Revolving Credit Facility \| New Credit Facility and Bond Indenture
Debt Instrument [Line Items]
Maximum borrowings under credit facility	$ 400,000,000.0
Debt instrument term	5 years
Revolving line of credit	$ 500,000,000
Revolving Credit Facility \| Revolving credit facility - U.S. dollar borrowings
Debt Instrument [Line Items]
Average interest rate on outstanding borrowings		4.00%
LIBOR \| Revolving Credit Facility \| New Credit Facility and Bond Indenture
Debt Instrument [Line Items]
Basis spread on variable interest rate		1.75%
LIBOR \| Term loan facility \| New Credit Facility and Bond Indenture
Debt Instrument [Line Items]
Basis spread on variable interest rate		2.00%
Base Rate \| Revolving Credit Facility \| New Credit Facility and Bond Indenture
Debt Instrument [Line Items]
Basis spread on variable interest rate		0.75%
Base Rate \| Term loan facility \| New Credit Facility and Bond Indenture
Debt Instrument [Line Items]
Basis spread on variable interest rate		1.00%