Debt (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Long-term debt [Abstract]
Long-term debt, Total	$ 295,173	$ 309,744
Current portion of long-term debt, net	(18,000)	(27,000)
Total long-term debt, net	277,173	282,744
Term loan, mandatory principal payments during term, with remaining principal balance due December 2015, interest at adjusted LIBOR plus 3.75% (combined rate of 4.22% at June 30, 2012 and 4.30% at December 31, 2011) [Member]
Long-term debt [Abstract]
Long-term debt, Total	173,000	190,000
$100 million revolving loan facility, due December 2015, interest at adjusted LIBOR plus applicable margin [Member]
Long-term debt [Abstract]
Long-term debt, Total
2010 Convertible Notes - senior subordinated convertible notes; due March1, 2017; cash interest at 3.0%; net of unamortized original issue discount ("OID") of $27,827 and $30,256, respectively [Member]
Long-term debt [Abstract]
Long-term debt, Total	$ 122,173	$ 119,744