Other Assets - Schedule of Notes Receivable Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Recovery of / (provision for) expected credit losses		$ 368	$ 3,319
Accounting Standards Update [Extensible List]		us-gaap:AccountingStandardsUpdate201613Member		us-gaap:AccountingStandardsUpdate201613Member	us-gaap:AccountingStandardsUpdate201602Member
Loan Receivables
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning of period balance	$ (46)	$ 0
Recovery of / (provision for) expected credit losses	(20)	368
Write-offs	1	1
End of period balance	(65)	(65)		$ 0
Loan Receivables | Impact of adopting Topic 326
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning of period balance	0	(434)
End of period balance				(434)
Hardware Financing Receivables
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning of period balance	(37)	(16)
Recovery of / (provision for) expected credit losses	6	0
Write-offs	0	0
End of period balance	(31)	(31)		(16)
Hardware Financing Receivables | Impact of adopting Topic 326
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning of period balance	$ 0	$ (15)
End of period balance				$ (15)