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Summary of Significant Accounting Policies - Narrative (Detail)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Minimum
Schedule Of Significant Accounting Policies [Line Items]
Additional terms of termination option			1 year
Maximum
Schedule Of Significant Accounting Policies [Line Items]
Additional terms of termination option			10 years
GE | Credit Concentration Risk | Receivables
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk (in percentage)			10.00%		16.00%
GE | Revenue Concentration Risk | Revenue From Contract With Customer
Schedule Of Significant Accounting Policies [Line Items]
Concentration risk (in percentage)	9.00%	12.00%	10.00%	13.00%

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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