Leases - Narrative (Details) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2021 USD ($)	Mar. 31, 2021 hub	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)	Mar. 31, 2018 hub
Lessee, Lease, Description [Line Items]
Operating lease expense	$ 920		$ 435	$ 2,824	$ 2,688
Short-term lease costs	66		65	181	188
Sublease income	34		34	101	101
Finance lease term							5 years
Number of satellite hubs leased | hub							3
Number of satellite hubs disposed | hub		2
Finance lease, gross cost	121,455			121,455		$ 114,265
Finance lease, accumulated depreciation	61,491			$ 61,491		$ 57,992
Leased assets, useful life				5 years
Capital asset depreciation expense	45		45	$ 136	136
Net investment in lease, current	3,962			3,962
Net investment in lease, noncurrent	6,905			6,905
Sales-type lease, interest income	$ 218		$ 223	$ 670	$ 623
Lessor, operating lease, term of contract	3 years			3 years
Lessor, operating lease, gross costs	$ 1,060			$ 1,060
Lessor, operating lease, accumulated depreciation	89			$ 89
Lessor, operating lease, useful life				5 years
Depreciation expense	43			$ 88
Lease revenue	$ 68			$ 141
Minimum
Lessee, Lease, Description [Line Items]
Sales-type leases, term of contracts	3 years			3 years
Maximum
Lessee, Lease, Description [Line Items]
Sales-type leases, term of contracts	5 years			5 years
Assets Held Under Finance Leases
Lessee, Lease, Description [Line Items]
Finance lease, gross cost	$ 1,268			$ 1,268
Finance lease, accumulated depreciation	$ 664			$ 664
Leased assets, useful life				7 years