Debt (Details Textual) $ in Millions	6 Months Ended
	Jun. 30, 2016 USD ($)	Jun. 17, 2016	Sep. 24, 2015 USD ($)	Jul. 09, 2014 USD ($)
Line of Credit Facility [Line Items]
Debt Instrument, Maturity Date	Jul. 09, 2019
Debt Instrument Maturities Quarterly Repayments of Principal			$ 3.8
Revolving Credit Facility, Capacity Available for Letter of Credit	$ 40.0
Outstanding letters of credit	22.8
Total availability under revolving credit facility	$ 153.7
Average interest rate on credit agreement	4.00%
Eurocurrency | Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)	2.00%
Eurocurrency | Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)	3.50%
Base Rate | Minimum
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)	1.00%
Base Rate | Maximum
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)	2.50%
Four Quarters Ended June 30, 2016
Line of Credit Facility [Line Items]
Maximum cash flow leverage ratio		4.50
Minimum fixed charge coverage ratio		1.15
Four Quarters Ending September 30, 2016
Line of Credit Facility [Line Items]
Maximum cash flow leverage ratio		4.00
Minimum fixed charge coverage ratio		1.15
Four Quarters Ending December 31, 2016
Line of Credit Facility [Line Items]
Maximum cash flow leverage ratio		3.75
Minimum fixed charge coverage ratio		1.15
Four Quarters Ending March 31, 2017
Line of Credit Facility [Line Items]
Maximum cash flow leverage ratio		3.50
Four Quarters Ending June 30, 2017
Line of Credit Facility [Line Items]
Maximum cash flow leverage ratio		3.25
All Period Thereafter
Line of Credit Facility [Line Items]
Maximum cash flow leverage ratio		3.00
Minimum fixed charge coverage ratio		1.25
Revolving credit facility
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			400.0	$ 350.0
Line of Credit Facility, Current Borrowing Capacity			300.0
Term loan
Line of Credit Facility [Line Items]
Term loan			$ 300.0	$ 200.0