Leases - Operating Leases - Data center colocation lease (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2019
Operating leases
Operating lease right-of-use assets	$ 17,743		$ 88,300
Lease liability	$ 23,228		94,900
Asset impairment charge
Weighted-average discount rate of operating leases (as a percent)	5.80%
Lease cost	$ 19,490
Data Center Lease, Boston, Massachusetts
Operating leases
Annual rent escalation (as a percent)	4.00%
Operating lease right-of-use assets			600
Lease liability	$ 400		$ 600
Asset impairment charge
Weighted-average discount rate of operating leases (as a percent)	6.00%
Lease cost	$ 200
Rent expense		$ 200
Data Center Lease, Boston, Massachusetts | Selling, general and administrative
Asset impairment charge
Asset impairment charge	$ 500