Amount of debt offered for exchange by company.

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Amount of debt tendered for exchange by the holders.

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Debt instrument redemption price as percentage of principal amount prior quarter.

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Expense recognized for redemption of senior notes.

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Interest coverage ratio required in two years and each quarter thereafter.

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Leverage ratio required each quarter thereafter.

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- Definition

Maximum percentage of stock of certain first-tier foreign subsidiaries pledged to secure senior credit facility.

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Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

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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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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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Amount of the required periodic payment applied to principal.

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

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. 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 in the next 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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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Long-Term Debt and Financing Arrangements - Additional Information (Details) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended	15 Months Ended	18 Months Ended
	Jun. 30, 2016 USD ($)	Dec. 31, 2019 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2019 USD ($)	Jul. 13, 2016 USD ($)	Jun. 13, 2016	Jun. 06, 2016 USD ($)	Dec. 31, 2015 USD ($)
Debt Instrument [Line Items]
Maximum percentage of stock of certain first-tier foreign subsidiaries pledged to secure senior credit facility	66.00%		66.00%
Maximum borrowing capacity	$ 1,200,000		$ 1,200,000
Debt outstanding	1,282,000		$ 1,282,000							$ 1,124,000
Interest coverage ratio (minimum) effective from March 31, 2014 through March 22, 2017			2.75
Leverage Ratio Required (Maximum) for future quarters			3.50
Tranche Term Facility
Debt Instrument [Line Items]
Outstanding debt	278,000		$ 278,000
Debt outstanding	276,000		276,000
Debt issuance costs	2,000		2,000
Principal payments excluded from current liabilities	19,000		19,000
5.375% Senior Notes Due 2024
Debt Instrument [Line Items]
Outstanding debt	225,000		225,000
Debt outstanding	221,000		221,000
Debt issuance costs	$ 4,000		$ 4,000
Stated percentage	5.375%		5.375%
Five Percent Senior Notes Due July 15 2026 [Member] [Domain]
Debt Instrument [Line Items]
Outstanding debt	$ 500,000		$ 500,000
Debt outstanding	492,000		492,000
Debt issuance costs	8,000		8,000
6.875% senior notes due December 2020
Debt Instrument [Line Items]
Outstanding debt	175,000		175,000
Debt outstanding	173,000		173,000
Debt issuance costs	$ 2,000		$ 2,000
Stated percentage	6.875%		6.875%
Amount Of Debt Offered For Exchange By Company									$ 500,000
Amount Of Debt Tendered For Exchange By Holders									$ 325,000
Debt Instrument Redemption Price As Percentage Of Principal Amount Prior Quarter								103.81%
Expense Recognized For Redemption Of Senior Notes	$ 16,000
6.875% senior notes due December 2020 \| Subsequent Event
Debt Instrument [Line Items]
Amount Of Debt Tendered For Exchange By Holders							$ 175,000
Debt Instrument Redemption Price As Percentage Of Principal Amount Prior Quarter							103.438%
Other Debt
Debt Instrument [Line Items]
Unsecured debt	91,000		$ 91,000
Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	1,200,000		1,200,000
Outstanding debt	107,000		107,000
Unused borrowing capacity	1,093,000		1,093,000
Revolving Credit Facility \| Letter of Credit
Debt Instrument [Line Items]
Outstanding debt	0		0
Revolving Credit Facility \| Tranche Term Facility
Debt Instrument [Line Items]
Outstanding debt	278,000		278,000
Debt outstanding	276,000		276,000
Debt issuance costs	$ 2,000		$ 2,000
Future payment \| Tranche Term Facility
Debt Instrument [Line Items]
Repayment of term loan		$ 195,000		$ 5,625	$ 3,750	$ 7,500