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Revenue Recognition - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2019 USD ($) Customer	Dec. 31, 2018 USD ($) Customer	Dec. 31, 2017 USD ($) Customer
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Impairment losses on contract assets | $	$ 0	$ 0	$ 0
Customer Concentration Risk [Member] | Revenue [Member]
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Concentration risk, number of customers | Customer	0	0	0
Concentration risk, percentage	10.00%	10.00%	10.00%

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Concentration risk number of customers.

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Amount of impairment loss for asset recognized from cost incurred to obtain or fulfill contract with customer.

+ References

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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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