XML 94 R81.htm IDEA: XBRL DOCUMENT v3.21.1
REVENUE RECOGNITION - Summary of Significant Changes in Unbilled Receivables and Deferred Liabilities Balances (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Deferred Revenue (Increase) Decrease    
Balance at December 31, 2020 $ (162,301) $ (144,862)
Revenue recognized that was previously included in deferred revenue 33,439 38,749
Increases due to cash received (53,000) (43,685)
Cumulative catch-up adjustment arising from changes in estimates of transaction price 3,738 367
Net change (15,823) (4,569)
Balance at March 31, 2021 (178,124) (149,431)
Unbilled Receivables Increase (Decrease)    
Balance at December 31, 2020 10,429 1,362
Unbilled receivables recognized 20,471 1,395
Transferred to receivables from unbilled receivables (6,000)  
Net change 14,471 1,395
Balance at March 31, 2021 $ 24,900 $ 2,757