Debt (Details) In Thousands, unless otherwise specified			6 Months Ended					0 Months Ended							0 Months Ended					0 Months Ended						6 Months Ended		6 Months Ended
	Jun. 30, 2014 USD ($)	Dec. 31, 2013 USD ($)	Jun. 30, 2014 Convertible Debt [Member] 3.375% Convertible Notes [Member] USD ($)	Jun. 24, 2014 Convertible Debt [Member] 3.375% Convertible Notes [Member] USD ($)	Jun. 16, 2014 Convertible Debt [Member] 3.375% Convertible Notes [Member] USD ($)	Dec. 31, 2013 Convertible Debt [Member] 3.375% Convertible Notes [Member] USD ($)	Jul. 16, 2014 Convertible Debt [Member] 3.375% Convertible Notes [Member] Subsequent Event [Member] USD ($)	Sep. 27, 2013 Revolving Credit Agreement [Member] USD ($)	Jun. 30, 2014 Revolving Credit Agreement [Member] USD ($)	Dec. 31, 2013 Revolving Credit Agreement [Member] USD ($)	Jun. 30, 2014 Revolving Credit Agreement [Member] Euro Member Countries, Euro USD ($)	Jun. 30, 2014 Revolving Credit Agreement [Member] Euro Member Countries, Euro EUR (€)	Dec. 31, 2013 Revolving Credit Agreement [Member] Euro Member Countries, Euro USD ($)	Dec. 31, 2013 Revolving Credit Agreement [Member] Euro Member Countries, Euro EUR (€)	Sep. 27, 2013 Revolving Credit Agreement [Member] London Interbank Offered Rate (LIBOR) [Member] Minimum [Member]	Sep. 27, 2013 Revolving Credit Agreement [Member] London Interbank Offered Rate (LIBOR) [Member] Maximum [Member]	Sep. 27, 2013 Revolving Credit Agreement [Member] EUR (€)	Dec. 31, 2013 Revolving Credit Agreement [Member] Minimum [Member] USD ($)	Dec. 31, 2013 Revolving Credit Agreement [Member] Maximum [Member]	Sep. 27, 2013 Revolving Credit Agreement [Member] London Interbank Offered Rate (LIBOR) [Member]	Dec. 31, 2013 Revolving Credit Agreement [Member] Adjusted for Certain Acquisitons [Member] Maximum [Member]	Jun. 30, 2014 Lines of Credit and Overdrafts [Member] USD ($)	Dec. 31, 2013 Lines of Credit and Overdrafts [Member] USD ($)	Jun. 30, 2014 Foreign Bank Borrowings [Member] USD ($)	Dec. 31, 2013 Foreign Bank Borrowings [Member] USD ($)	Jun. 30, 2014 Lines of Credit [Member] USD ($)	Dec. 31, 2013 Lines of Credit [Member] USD ($)	Jun. 30, 2014 Bank Overdrafts [Member] USD ($)	Dec. 31, 2013 Bank Overdrafts [Member] USD ($)	Jun. 30, 2014 Capital Lease Obligations [Member] USD ($)	Dec. 31, 2013 Capital Lease Obligations [Member] USD ($)
Debt Instrument [Line Items]
Carrying amount of debt			$ 55,636			$ 55,636			$ 498,842	$ 487,920	$ 117,942	€ 86,420	$ 157,320	€ 114,000										$ 135	$ 405					$ 4,038	$ 3,120
Fair value of debt	601,031	563,886	75,845			76,569			508,354	482,431												12,265	1,074	136	410					4,431	3,402
Unamortized debt discount			0			(731)
Borrowings under lines of credit and overdrafts	12,265	1,074																				12,265	1,074			10,500	1,000	1,765	74
Total debt, net of unamortized discounts	570,916	547,424
Less current maturities	(68,971)	(57,083)
Long-term debt	501,945	490,341
Stated interest rate			3.375%						1.47%	1.36%
Convertible debt				55,412
Convertible note repurchases, par value					224		32,875
Line of credit facility, maximum borrowing capacity								750,000									500,000									40,000
Line of credit facility with accordian feature, maximum borrowing capacity								1,000,000
Variable rate basis																				LIBOR
Variable basis spread															1.10%	1.70%
Payments of debt issuance costs								1,261
Remaining borrowing capacity									251,158	262,080
Debt covenant ratio of senior debt to EBITDA																			3.25		3.50
Debt covenant ratio of total debt to EBITDA																			4.00		4.25
Debt covenant ratio of EBITDA to cash interest expense																		4.25
Debt covenant, threshold price of acquisition permitting higher ratio limits																		$ 150,000
Line of credit, interest rate at period end																										1.15%	2.13%
Repayment period																										1 month		2 days
Days Required for Closing Stock Price to be Greater or Equal to Threshold Percentage of Conversion Price			20 days
Total Measurement Days for Closing Stock Price to be Greater or Equal to Threshold Percentage of Conversion Price			30 days
Minimum Ratio Of Stock Price To Conversion Price For Conversion			130.00%