Route and Customer Acquisition Costs - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Capitalized Contract Cost [Line Items]
Gross payments due	$ 6,400	$ 7,400
Net present value of payments due	5,700	6,500
Current portion of payments due	1,608	1,700
Customer acquisition cost asset	17,700	18,700
Capitalized contract cost, subject to claw back	1,700	2,200
Amortization expense (decrease in expense) on route and customer acquisition costs	$ 1,800	$ 1,700	$ 3,900