Business Segments and Geographic Information (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jul. 01, 2012	Apr. 01, 2012	Jan. 01, 2012	Oct. 02, 2011	Jul. 03, 2011	Apr. 03, 2011	Dec. 31, 2012	Jan. 01, 2012	Jan. 02, 2011
Geographical Information
Revenues	$ 378,731	$ 369,115	$ 371,174	$ 360,042	$ 354,473	$ 354,728	$ 356,012	$ 341,959	$ 1,479,062	$ 1,407,172	$ 1,084,592
Property and equipment, net	1,687,159				1,688,356				1,687,159	1,688,356
U.S. operations
Geographical Information
Revenues									1,267,335	1,205,775	906,025
Property and equipment, net	1,680,038				1,683,124				1,680,038	1,683,124
Australia operations
Geographical Information
Revenues									159,444	150,753	130,738
Property and equipment, net	5,634				4,296				5,634	4,296
South African operations
Geographical Information
Revenues									20,029	21,357	19,231
Property and equipment, net	234				334				234	334
United Kingdom operations
Geographical Information
Revenues									32,254	29,287	28,598
Property and equipment, net	$ 1,253				$ 602				$ 1,253	$ 602