Long-Lived Assets - Summary of Aggregate Amortization Related to Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Acquired customer contracts
Finite Lived Intangible Assets [Line Items]
Total amortization expense	$ 9,963	$ 10,374	$ 7,898
Acquired software
Finite Lived Intangible Assets [Line Items]
Total amortization expense	1,853	2,229	1,801
Internal use software
Finite Lived Intangible Assets [Line Items]
Total amortization expense	13,216	10,641	9,517
Software
Finite Lived Intangible Assets [Line Items]
Total amortization expense	$ 15,069	$ 12,870	$ 11,318