Summary of significant accounting policies - Basis of presentation and consolidation (Details) - USD ($) $ in Thousands			12 Months Ended
	Jan. 01, 2019	Jan. 01, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Adoption of ASC 606
Accumulated deficit			$ (158,066)	$ (140,973)
Accounts receivable, net		$ 25,079	27,716	33,350
Prepaid expenses and other current assets		6,539	8,388	8,235
Other assets		7,903	11,264	9,309
Deferred revenue, current		75,884	65,292	61,229
Deferred revenue, net of current portion		128,588	159,462	166,660
Non-controlling interests			394	1,238
Revenue			237,416	263,790	$ 250,821
Non-controlling interests			(647)	19	$ 1,489
Lease, Practical Expedients, Package [true false]	true
Adoption of ASC 842
Operating lease right-of-use assets			12,876	$ 15,196
Operating lease right-of-use liabilities			$ 17,119
Adjustment for adoption
Adoption of ASC 606
Accounts receivable, net		(1,069)
Prepaid expenses and other current assets		170
Other assets		(2,179)
Deferred revenue, current		14,176
Deferred revenue, net of current portion		(20,580)
ASC 842
Adoption of ASC 842
Operating lease right-of-use assets	$ 16,916
Operating lease right-of-use liabilities	$ 22,338
ASC 606 | As per ASC 605
Adoption of ASC 606
Accounts receivable, net		26,148
Prepaid expenses and other current assets		6,369
Other assets		10,082
Deferred revenue, current		61,708
Deferred revenue, net of current portion		149,168
ASC 606 | Adjustment for adoption
Adoption of ASC 606
Accumulated deficit		3,257
Non-controlling interests		$ 69
Chicago Concourse Development Group, LLC
Basis of presentation and consolidation
Percentage of ownership in subsidiaries			70.00%
Boingo Holding Participacoes Ltda.
Basis of presentation and consolidation
Percentage of ownership in subsidiaries			75.00%