Debt Schedule of Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014
Debt Instrument [Line Items]
Total debt	$ 371,212
Current portion of debt	11,250	$ 11,250	$ 11,250	$ 30,000	$ 30,000	$ 30,000	$ 30,000	$ 28,125
Long-term debt	359,962	$ 369,457	$ 361,708	$ 331,310	293,969	$ 280,000	$ 297,500	$ 320,000
USD Denominated Term Loan [Member]
Debt Instrument [Line Items]
Loans Payable to Bank	219,375				232,500
Line of Credit [Member]
Debt Instrument [Line Items]
Long-term Line of Credit	151,837				91,469
Secured Debt [Member]
Debt Instrument [Line Items]
Total debt	371,212				323,969
Current portion of debt	11,250				30,000
Long-term debt	$ 359,962				$ 293,969