Debt and Credit Arrangements Senior Credit Facility and Senior Secured Revolving Credit Facility (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Debt Instrument [Line Items]
Financing costs amortization	$ 326	$ 326	$ 979	$ 979
Senior Credit Facility [Member]
Debt Instrument [Line Items]
Term of Senior Credit Facility			5 years
Line of Credit Facility, Maximum Borrowing Capacity	375,000		375,000
Debt Issuance Cost			1,445
Line of Credit Facility, Interest Rate Description			Loans under the Senior Credit Facility bear interest, at the applicable Borrower's election, at either LIBOR or the greatest of (a) the JPMorgan prime rate in effect on such day, (b) the Federal Funds Effective Rate in effect on such day plus 1/2 of 1% or (c) the Adjusted LIBOR Rate (as defined in the Restated Credit Facility) for a one month interest period on such day (or if such day is not a business day, the immediately preceding business day) plus 1%, plus a margin that varies with the Company's leverage ratio.
Fronting Fee Percentage Charged For Issuance Of Letters Of Credit	0.125%		0.125%
Line Of Credit Facility Initial Percentage Of Term Loan Payable Quarterly Due To Restated Credit Facility	5.00%		5.00%
Initial Duration Of Quarterly Payments On Term Loan Under The Terms Of The Restated Credit Facility			3 years
Line Of Credit Facility Final Percentage Of Term Loan Payable Quarterly Due To Restated Credit Facility	10.00%		10.00%
Final Duration Of Quarterly Payments On Term Loan Under The Terms Of The Restated Credit Facility			2 years
Line of Credit Facility, Covenant Terms			Significant financial covenants for the Senior Credit Facility include a leverage ratio and an interest ratio.
Maximum Percentage Of Capital Stock Guaranteed By Company's Material Non-U.S. Subsidiaries For Obligations Under The Senior Credit Facility	65.00%		65.00%
Debt Instrument, Covenant Compliance			At September 30, 2014, the Company was in compliance with all covenants.
Debt Instrument, Fair Value Disclosure, Narrative			The fair value of the term loan portion of the Company’s Senior Credit Facility was estimated based on the present value of the underlying cash flows discounted using market interest rates. Under this method, the fair value of the Company’s Term Loan approximated its carrying amount as of September 30, 2014 and December 31, 2013.
Senior Credit Facility [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	75,000		75,000
Financing costs amortization	148	148	446	446
Long-term Debt, Gross	65,625		65,625
Senior Credit Facility [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	300,000		300,000
Letters of Credit Outstanding, Amount	31,816		31,816
Line of Credit Facility, Remaining Borrowing Capacity	268,184		268,184
Senior Credit Facility [Member] | Revolving Credit Facility Sub-limit - Swingline [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	25,000		25,000
Senior Credit Facility [Member] | Revolving Credit Facility Sub-limit - Letters of Credit [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	100,000		100,000
Senior Credit Facility [Member] | Revolving Credit Facility Sub-limit - Foreign Currency [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	50,000		50,000
Senior Credit Facility [Member] | Revolving Credit Facility Sub-limit - Foreign Borrower [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	50,000		50,000
Senior Credit Facility [Member] | Revolving Credit Facility - Expansion Option [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	150,000		150,000
Senior Secured Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Covenant Terms			Significant financial covenants for the Senior Secured Revolving Credit Facility include a minimum liquidity ratio equal to the principal amount of the Convertible Notes six months prior to the maturity date of the Convertible Notes, a maximum leverage ratio of 3.25 and a minimum interest coverage to EBITDA ratio of 3.0. The required leverage ratio can be relaxed, upon notification to the lenders, to 3.75 for up to four consecutive fiscal quarters, for acquisitions and plant expansions of $100,000 or greater.
Senior Secured Revolving Credit Facility [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Term of Senior Credit Facility			5 years
Line of Credit Facility, Maximum Borrowing Capacity	450,000		450,000
Senior Secured Revolving Credit Facility [Member] | Revolving Credit Facility Sub-limit - Swingline [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	25,000		25,000
Senior Secured Revolving Credit Facility [Member] | Revolving Credit Facility Sub-limit - Letters of Credit [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	100,000		100,000
Senior Secured Revolving Credit Facility [Member] | Revolving Credit Facility Sub-limit - Foreign Currency [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	100,000		100,000
Senior Secured Revolving Credit Facility [Member] | Revolving Credit Facility Sub-limit - Foreign Borrower [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	100,000		100,000
Senior Secured Revolving Credit Facility [Member] | Revolving Credit Facility - Expansion Option [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 200,000		$ 200,000
Minimum [Member] | Senior Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage			0.25%
Line of Credit Facility, Participation Fee Percentage			1.50%
Maximum [Member] | Senior Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage			0.40%
Line of Credit Facility, Participation Fee Percentage			3.00%