Debt (Details Textual)
0 Months Ended 3 Months Ended 3 Months Ended 3 Months Ended
Mar. 17, 2015
USD ($)
Mar. 17, 2015
EUR (€)
Mar. 31, 2015
USD ($)
Mar. 31, 2014
USD ($)
Mar. 31, 2015
Interest Rate Swap
USD ($)
Dec. 31, 2014
Interest Rate Swap
USD ($)
Mar. 31, 2015
Term Loan Facility
USD ($)
Oct. 04, 2013
Term Loan Facility
USD ($)
Mar. 31, 2015
Revolving Credit Facility
USD ($)
Dec. 31, 2014
Revolving Credit Facility
USD ($)
Oct. 04, 2013
Revolving Credit Facility
USD ($)
Mar. 31, 2015
Senior Credit Facility
USD ($)
Dec. 31, 2014
Senior Credit Facility
USD ($)
Mar. 31, 2016
Senior Credit Facility
Scenario, Forecast
USD ($)
Dec. 31, 2015
Senior Credit Facility
Scenario, Forecast
USD ($)
Sep. 30, 2015
Senior Credit Facility
Scenario, Forecast
USD ($)
Jun. 30, 2015
Senior Credit Facility
Scenario, Forecast
USD ($)
Mar. 17, 2015
2022 EUR Senior Notes
USD ($)
Mar. 17, 2015
2022 EUR Senior Notes
EUR (€)
Line of Credit Facility [Line Items]                                      
Debt Instrument, Face Amount               $ 400,000,000                   $ 500,000,000 € 500,000,000
Line of Credit Facility, Maximum Borrowing Capacity                     1,000,000,000                
Revolving Credit Facility                 0 0                  
Letters of credit outstanding                       78,900,000 76,800,000            
Line of Credit Facility, Current Borrowing Capacity                 921,100,000 923,200,000                  
Line of credit, commitment fee (as a percentage)                       0.175%              
Payments on long-term debt     10,000,000 10,000,000     10,000,000                        
Credit Facilities Scheduled Repayments Due in Next Two Quarters                               10,000,000 10,000,000    
Credit Facilities Scheduled Repayments Due In the Fourth Quarter                             15,000,000        
Credit Facilities Scheduled Repayments Due In the First Quarter of Next Year                           15,000,000          
Derivative, notional amount         25,000,000 40,000,000                          
Domestic subsidiaries unconditional guarantee     100.00%                                
Debt Instrument, Interest Rate Terms 0.0125 0.0125                                  
Price of senior notes, stated as percentage of principal amount     99.336%                                
Proceeds from Issuance of Debt $ 523,400,000 € 494,000,000