Commitments and Contingencies - Narrative (Details) - USD ($) $ in Thousands							6 Months Ended
	Feb. 22, 2021	Oct. 10, 2019	Oct. 01, 2019	Jul. 23, 2019	Jun. 29, 2017	May 05, 2017	Jun. 30, 2020	Dec. 31, 2019
Loss Contingencies [Line Items]
Implementation fee				$ 600
Accrued expenses and other payables							$ 12,692	$ 13,616
Unconditional purchase obligation							27,950
Forecast
Loss Contingencies [Line Items]
Implementation fee	$ 400
Pccw Global Limiited
Loss Contingencies [Line Items]
Credit voucher				$ 28,100
Payments for credit voucher							100
Accrued expenses and other payables							400
Unconditional purchase obligation							27,600
Debt Instrument, Redemption, Period One
Loss Contingencies [Line Items]
Credit voucher, minimum monthly charge							7,300
Debt Instrument, Redemption, Period Two
Loss Contingencies [Line Items]
Credit voucher, minimum monthly charge							12,900
Debt Instrument, Redemption, Period Three
Loss Contingencies [Line Items]
Credit voucher, minimum monthly charge							19,700
Debt Instrument, Redemption, Period Four
Loss Contingencies [Line Items]
Credit voucher, minimum monthly charge							27,600
Artilium Africa | Pending Litigation
Loss Contingencies [Line Items]
Loss contingency, damages sought, value			$ 30,000
Artilium Africa and Tristar Africa Telecom | Pending Litigation
Loss Contingencies [Line Items]
Loss contingency, damages sought, value		$ 200
Lawsuit By Deutsche Telekom A.g.
Loss Contingencies [Line Items]
Loss contingency, damages sought, value							800
Lawsuit By Stephen Brown
Loss Contingencies [Line Items]
Loss contingency, damages sought, value							$ 800
Number of years for which expenses incurred							5 years
Unpaid Legal Fees
Loss Contingencies [Line Items]
Loss contingency, damages sought, value					$ 800	$ 800
Loss contingency accrual							$ 100