Segment and Related Information - Revenue by Major Customers (Details) - Customer Concentration Risk - Revenue Benchmark	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenue, Major Customer [Line Items]
Concentration risk, percentage	100.00%	100.00%	100.00%	100.00%
Restaurant/Retail | Dairy Queen
Revenue, Major Customer [Line Items]
Concentration risk, percentage	6.00%	13.00%	7.00%	13.00%
Restaurant/Retail | Yum! Brands, Inc.
Revenue, Major Customer [Line Items]
Concentration risk, percentage	11.00%	11.00%	12.00%	10.00%
Restaurant/Retail | McDonald’s Corporation
Revenue, Major Customer [Line Items]
Concentration risk, percentage	12.00%	6.00%	11.00%	7.00%
Government | U.S. Department of Defense
Revenue, Major Customer [Line Items]
Concentration risk, percentage	23.00%	32.00%	27.00%	34.00%
Government | All Others
Revenue, Major Customer [Line Items]
Concentration risk, percentage	48.00%	38.00%	43.00%	36.00%