Debt and Credit Agreements (Details 3) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Total debt obligations	$ 673,410	$ 880,835
Less: deferred financing costs	(18,597)	(10,130)
Total debt obligations, net of deferred financing costs	654,813	870,705
Less: current maturities of long-term debt	(25,574)	(25,084)
Long-term debt	629,239	845,621
Maturities of Long-term Debt [Abstract]
2018	9,924
2019	6,217
2020	5,664
2021	103,531
Revolving Credit Facility
Debt Instrument [Line Items]
Total debt obligations	$ 98,000	$ 143,000
Variable interest rate	3.60%	3.20%
Senior Notes \| 5.75% notes due May 15, 2018
Debt Instrument [Line Items]
Total debt obligations	$ 0	$ 449,005
Stated interest rate	0.00%	5.75%
Term Loan \| Term Loan Facility 2015
Debt Instrument [Line Items]
Total debt obligations		$ 250,000
Variable interest rate		2.90%
Term Loan \| Term Loan Facility 2016
Debt Instrument [Line Items]
Total debt obligations	$ 550,000
Variable interest rate	6.00%
Other financing payable in varying amounts due principally through 2018 with a weighted-average interest rate of 2.7% and 9.4% at December 31, 2012 and 2011, respectively
Debt Instrument [Line Items]
Total debt obligations	$ 25,410	$ 38,830
Weighted average interest rate	5.70%	5.60%

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