Revenue Recognition - Capitalized Service Contract Costs (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Capitalized Contract Cost [Roll Forward]      
Capitalized costs, beginning balance $ 107,236 $ 42,314 $ 35,565
Royalties and sales commissions – additions 68,938 43,273 18,984
Revenue share and cost per acquisition fees – additions 98,747 52,193 6,284
Amortization of capitalized costs (71,850) (30,544) (18,519)
Capitalized costs, ending balance $ 203,071 $ 107,236 $ 42,314