Long-Lived Assets - Summary of Aggregate Amortization Related to Client Contract Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Capitalized Contract Cost [Line Items]
Total client contract costs, aggregate amortization	$ 20,779	$ 23,381
Client contract incentives
Capitalized Contract Cost [Line Items]
Total client contract costs, aggregate amortization	6,018	11,052
Capitalized costs
Capitalized Contract Cost [Line Items]
Total client contract costs, aggregate amortization	12,625	10,304
Capitalized commission fees
Capitalized Contract Cost [Line Items]
Total client contract costs, aggregate amortization	$ 2,136	$ 2,025