Debt (Schedule of Long-Term Debt) (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015	Jan. 31, 2013
Debt Instrument [Line Items]
Total debt	$ 209,637,000	$ 209,282,000
Unamortized original issue discount	(3,163,000)	(3,918,000)
Less current maturities	400,000	400,000
Total long-term debt	209,237,000	208,882,000
Senior Subordinated 6.25% Notes
Debt Instrument [Line Items]
Total debt	$ 210,000,000	$ 210,000,000
Senior Subordinated Notes, interest rate	6.25%	6.25%	6.25%
Other debt
Debt Instrument [Line Items]
Total debt	$ 2,800,000	$ 3,200,000