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Line of Credit Facility, Increase in Additional Principal Amount

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Pledged equity interest in foreign subsidiaries

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

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

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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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Weighted average interest rate of debt outstanding.

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

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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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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 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 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 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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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 outflow to repay long-term debt that is wholly or partially secured by collateral. Excludes repayments of tax exempt secured debt.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Long-Term Debt (Details) (USD $)	12 Months Ended			0 Months Ended
Long-Term Debt (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 28, 2014	May 16, 2013
Debt Instrument [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	$ 18,250,000
Document Period End Date	Dec. 31, 2014
Senior Secured Debt	415,125,000us-gaap_SecuredDebt	399,813,000us-gaap_SecuredDebt
Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums		15,000,000
Write off of Deferred Debt Issuance Cost	0	14,958,000	813,000
Pledged equity interest in foreign subsidiaries	65.00%
Weighted average interest rate	2.60%us-gaap_DebtWeightedAverageInterestRate
Long-term Debt, Maturities, Repayments of Principal in Year Two	18,250,000
Long-term Debt, Maturities, Repayments of Principal in Year Three	18,250,000
Long-term Debt, Maturities, Repayments of Principal in Year Four	180,063,000
Long-term Debt, Maturities, Repayments of Principal in Year Five	0
Long-term Debt, Maturities, Repayments of Principal after Year Five	180,312,000
Long-term Debt	415,125,000us-gaap_LongTermDebt
Maximum [Member]
Debt Instrument [Line Items]
Leverage Ratio in Latest Year of Debt Term	3.25
Leverage ratio	3.50
Revolving Loans and Term A Loans \| Eurodollar Rate or Base Rate [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate borrowings	2.50%
Revolving Loans and Term A Loans \| Eurodollar Rate or Base Rate [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate borrowings	1.75%
Term A Loans, Term B Loans and Revolving Loans [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity					500,000,000
Term-B Loan Facility due May 2020 [Member] \| Eurodollar [Member]
Debt Instrument [Line Items]
Basis spread on variable rate borrowings	2.50%
Term Loan Facility \| $100 million term A loan facility, due May 2017
Debt Instrument [Line Items]
Interest rate at year end	1.90%
Term Loan Facility \| Term A Loans, Term B Loans and Revolving Loans [Member]
Debt Instrument [Line Items]
Increase to borrowing capacity available under credit facility					100,000,000
Term Loan Facility \| Term-A Loan Facility due May 2018 [Member]
Debt Instrument [Line Items]
Senior Secured Debt	158,813,000	92,500,000
Face amount of term loan					100,000,000
Secured Debt, Increase in Additional Principal Amount				82,500,000
Term Loan Facility \| Term-B Loan Facility due May 2020 [Member]
Debt Instrument [Line Items]
Senior Secured Debt	180,312,000	262,813,000
Face amount of term loan					275,000,000
Repayments of Lines of Credit				82,500,000
Debt Instrument, Interest Rate, Stated Percentage					1.00%
Interest rate at year end	3.50%
Revolving Credit Facility
Debt Instrument [Line Items]
Letters of credit outstanding, amount	45,800,000
Revolving Credit Facility \| Revolving Credit Facility due May 2018 [Member]
Debt Instrument [Line Items]
Senior Secured Debt	76,000,000	44,500,000
Line of credit facility, maximum borrowing capacity					$ 125,000,000
Revolving Credit Facility \| Revolving Credit Facility due May 2018 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Revolving credit facility, unused portion, commitment fee percentage	0.40%
Revolving Credit Facility \| Revolving Credit Facility due May 2018 [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Revolving credit facility, unused portion, commitment fee percentage	0.25%
Revolving Credit Facility \| Revolving Credit Facility due May 2018 [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Interest rate at year end	0.17%
Revolving Credit Facility \| Revolving Credit Facility due May 2018 [Member] \| Spread [Member]
Debt Instrument [Line Items]
Interest rate at year end	2.00%