Financial Instruments (Financial Instruments Assets (Liabilities) Measured At Fair Value) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Financial Instruments And Fair Value Measurements [Line Items]
Cash and cash equivalents, Carrying Amount	$ 211,413	$ 140,500	$ 50,189	$ 28,328
Loans payable, Carrying Amount	(3,442)	(4,284)
Long-term debt, Carrying Amount	(410,221)	(307,727)
Foreign currency forward contracts, net, Carrying Amount	439	713
Cash and cash equivalents, Fair Value	211,413	140,500
Loans payable, Fair Value	(3,442)	(4,284)
Foreign currency forward contracts, net, Fair Value	439	713
Revolving Credit Line [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Carrying Amount	(105,000)
Long-term debt, Fair Value	(105,211)
Term Loan Facility [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Carrying Amount	(297,750)	(299,250)
Long-term debt, Fair Value	(308,929)	(310,453)
Other Long-Term Notes Payable [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Carrying Amount	(3,089)	(3,504)
Long-term debt, Fair Value	(2,522)	(2,861)
Level 1 [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Cash and cash equivalents, Fair Value	211,413	140,500
Level 2 [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Loans payable, Fair Value	(3,442)	(4,284)
Foreign currency forward contracts, net, Fair Value	439	713
Level 2 [Member] | Revolving Credit Line [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Fair Value	(105,211)
Level 2 [Member] | Term Loan Facility [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Fair Value	(308,929)	(310,453)
Level 2 [Member] | Other Long-Term Notes Payable [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Fair Value	$ (2,522)	$ (2,861)
Level 3 [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Cash and cash equivalents, Fair Value
Loans payable, Fair Value
Foreign currency forward contracts, net, Fair Value
Level 3 [Member] | Revolving Credit Line [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Fair Value
Level 3 [Member] | Term Loan Facility [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Fair Value
Level 3 [Member] | Other Long-Term Notes Payable [Member]
Financial Instruments And Fair Value Measurements [Line Items]
Long-term debt, Fair Value