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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).

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Including the current and noncurrent portions, the carrying value of convertible subordinated debt, as of the balance sheet date, initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. This form of debt can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder, and places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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Fair value as of the balance sheet date of all foreign currency derivative assets not designated as hedging instruments.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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Amount borrowed under the credit facility as of the balance sheet date.

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Fair Values of Financial Instruments Schedule of Fair Values of Financial Instruments (Details) In Thousands	Sep. 30, 2011 USD ($)	Dec. 31, 2010 USD ($)	Sep. 30, 2010 USD ($)	Dec. 31, 2009 USD ($)	Sep. 30, 2011 2011 Senior Secured Credit Facility [Member] USD ($)	Dec. 31, 2010 2011 Senior Secured Credit Facility [Member] USD ($)	Sep. 30, 2011 2011 Senior Secured Credit Facility [Member] USD Denominated Term Loan [Member] USD ($)	Dec. 31, 2010 2011 Senior Secured Credit Facility [Member] USD Denominated Term Loan [Member] USD ($)	Sep. 30, 2011 2007 Senior Secured Credit Facility [Member] USD Denominated Term Loan [Member] USD ($)	Dec. 31, 2010 2007 Senior Secured Credit Facility [Member] USD Denominated Term Loan [Member] USD ($)	Sep. 30, 2011 2007 Senior Secured Credit Facility [Member] EUR Denominated Term Loan [Member] USD ($)	Dec. 31, 2010 2007 Senior Secured Credit Facility [Member] EUR Denominated Term Loan [Member] USD ($)	Sep. 30, 2011 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 2 [Member] USD ($)	Dec. 31, 2010 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 2 [Member] USD ($)	Dec. 31, 2010 EUR Denominated Term Loan [Member] USD ($)	Dec. 31, 2010 EUR Denominated Term Loan [Member] EUR (€)
Assets
Cash and cash equivalents	$ 129,514	$ 169,477	$ 148,114	$ 121,893
Cash and cash equivalents, at fair value	129,514	169,477
Foreign exchange forwards, asset	175	63
Foreign exchange forwards, asset, at fair value													175	63
Liabilities
Term loans							296,252	0	0	218,642	0	174,031			174,000	132,400
Term loans, at fair value							296,252	0	0	219,462	0	174,684
Line of Credit Facility, Amount Outstanding					200,000	0
Line of Credit Facility, Fair Value of Amount Outstanding					200,000	0
Convertible senior subordinated debt	0	218,268
Convertible senior subordinated notes, at fair value	0	236,461
Interest rate swaps	0	6,820
Interest rate swaps, at fair value													0	6,820
Foreign exchange forwards, liability	342	457
Foreign exchange forwards, liability, at fair value													$ 342	$ 457