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Related Parties - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended	6 Months Ended
	Feb. 28, 2019	Jun. 30, 2018	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Liberty Global Affiliates
Related Party Transaction [Line Items]
Revenue from transactions with Liberty Global Affiliates			$ 1,989		$ 17,720
Amounts received in cash from Liberty Global Affiliates			$ 13,815		27,707
Rongke Xie
Related Party Transaction [Line Items]
Compensation paid				$ 74	$ 101
Rongke Xie \| Restricted Stock Units
Related Party Transaction [Line Items]
Number of shares granted	8	5
Vesting period		4 years
Aggregate fair value vested		$ 200
Selling, general and administrative expenses recognized				$ 22