Long-Term Debt (Schedule Of Long-Term Debt) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Debt Disclosure [Abstract]
Senior notes	$ 191,429	$ 227,143
Revolving credit facility	34,680	10,000
Capitalized lease and other obligations	2,688	3,264
Total long-term debt	228,797	240,407
Less: Current maturities	(38,403)	(38,978)
Total maturities due after one year	$ 190,394	$ 201,429