Other Long-Term Liabilities (Details) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Other Long-Term Liabilities [Abstract]
Vested amounts under the non-qualified deferred compensation plan	$ 6,600,000	$ 7,600,000
Current portions of the non-qualified deferred compensation plan	4,100,000	4,000,000
Estimated future plan payments under non-qualified deferred compensation plan [Abstract]
2013	4,100,000
2014	800,000
2015	300,000
2016	300,000
2017	100,000
Accrued performance cash amount	0	2,500,000
Accrued performance cash amount, current portion	2,000,000	6,000,000
Estimated future plan payments for performance cash awards [Abstract]
2013	$ 2,000,000