Segment and Related Information, Revenue By Major Customer (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Revenue, Major Customer [Line Items]
Percentage of revenue generated by customer (in hundredths)	100.00%	100.00%	100.00%	100.00%
McDonald's Corporation [Member]
Revenue, Major Customer [Line Items]
Percentage of revenue generated by customer (in hundredths)	16.00%	18.00%	20.00%	19.00%
Yum! Brands, Inc. [Member]
Revenue, Major Customer [Line Items]
Percentage of revenue generated by customer (in hundredths)	15.00%	14.00%	16.00%	14.00%
U.S. Department of Defense [Member]
Revenue, Major Customer [Line Items]
Percentage of revenue generated by customer (in hundredths)	39.00%	39.00%	37.00%	42.00%
All Others [Member]
Revenue, Major Customer [Line Items]
Percentage of revenue generated by customer (in hundredths)	30.00%	29.00%	27.00%	25.00%