Fair Value Measurements (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2012	Dec. 31, 2011	Jan. 02, 2011
Fair Value Measurements [Abstract]
Impairment of goodwill and other long-lived assets	$ 111,593	$ 0	$ 0	$ 0	$ 111,593	$ 0	$ 0