Represents term of option to extend credit facility after the maturity date specified in the agreement.

No definition available.

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The borrowing margin percentage rate, to which the higher of two alternative variable rates is added.

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The effective borrowing margin percentage rate, to which the higher of two alternative variable rates is added.

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No definition available.

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services.

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

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No definition available.

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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.

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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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No definition available.

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Weighted average interest rate of debt outstanding.

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No definition available.

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- Definition

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

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No definition available.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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.

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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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No definition available.

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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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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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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 third 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 second 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 cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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No definition available.

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Long-Term Debt and Capital Lease Obligations (Details) - USD ($) $ in Thousands			12 Months Ended
	Sep. 30, 2014	Jul. 23, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 09, 2011
Long-term Debt and Capital Lease Obligations
Capital lease obligations			$ 24,400	$ 24,600
Proceeds from issuance of debt				250,000
Gross cost of capital leased assets			39,300	34,800
Revolving Loan borrowings
Long-term Debt and Capital Lease Obligations
Revolving borrowings outstanding			0	0
Term Loan
Long-term Debt and Capital Lease Obligations
Revolving borrowings outstanding			234,400
Long-term Debt, Fiscal Year Maturity
2016			15,600
2017			25,000
2018			25,000
2019			168,800
Letter of Credit
Long-term Debt and Capital Lease Obligations
Letters of credit outstanding			$ 33,400	$ 32,900
2011 Credit Facility \| Revolving Loan borrowings
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity					$ 230,000
Commitment commission (as a percent)			0.375%
2011 Credit Facility \| Letter of Credit
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity					$ 70,000
Stated interest rate (as a percent)			1.875%
2011 Credit Facility \| U.S. dollar denominated loans \| Revolving Loan borrowings
Long-term Debt and Capital Lease Obligations
Borrowing margin (as a percent)			0.75%
2011 Credit Facility \| U.S. dollar denominated loans \| Overnight Federal Funds rate \| Revolving Loan borrowings
Long-term Debt and Capital Lease Obligations
Basis spread on variable rate (as a percent)			0.50%
2011 Credit Facility \| U.S. dollar denominated loans \| Eurodollar rate for one month \| Revolving Loan borrowings
Long-term Debt and Capital Lease Obligations
Basis spread on variable rate (as a percent)			1.00%
2011 Credit Facility \| Eurodollar denominated loans \| Eurodollar rate for selected interest period \| Revolving Loan borrowings
Long-term Debt and Capital Lease Obligations
Borrowing margin (as a percent)			1.75%
2014 Credit Facility
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity		$ 500,000
Term of option to extend credit facility		1 year
2014 Credit Facility \| Revolving Loan borrowings
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity		$ 250,000
Commitment commission (as a percent)			0.20%
2014 Credit Facility \| Term Loan
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity		250,000
2014 Credit Facility \| Letter of Credit
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity		$ 70,000
Stated interest rate (as a percent)			1.625%
2014 Credit Facility \| Revolving and Term Loan Borrowings
Long-term Debt and Capital Lease Obligations
Borrowing margin (as a percent)			0.50%
2014 Credit Facility \| Overnight Federal Funds rate \| Revolving and Term Loan Borrowings
Long-term Debt and Capital Lease Obligations
Basis spread on variable rate (as a percent)			0.50%
2014 Credit Facility \| Eurodollar rate for one month \| Revolving and Term Loan Borrowings
Long-term Debt and Capital Lease Obligations
Basis spread on variable rate (as a percent)			1.00%
2014 Credit Facility \| Eurodollar denominated loans \| Eurodollar rate for selected interest period \| Term Loan
Long-term Debt and Capital Lease Obligations
Proceeds from issuance of debt	$ 250,000
Effective borrowing margin (as a percent)			1.50%
Effective interest rate (as a percent)			1.9239%
Weighted average interest rate (as a percent)			1.6878%
2014 Credit Facility \| Eurodollar denominated loans \| Eurodollar rate for selected interest period \| Revolving and Term Loan Borrowings
Long-term Debt and Capital Lease Obligations
Borrowing margin (as a percent)			1.50%