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Revenue Recognition - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019
Disaggregation Of Revenue [Line Items] |  |
Period for credit risk identified | 30 days |
Sales revenues totaling | $ 17.0 |
Unbilled contract assets | $ 38.7 | $ 37.2
Period for warranties for rental equipment | 90 days |
Period for warranties for equipment manufactured | 1 year |
Deferred Income [Member] |  |
Disaggregation Of Revenue [Line Items] |  |
Customer contract liability | $ 11.3 | 17.5
Accounts Receivable [Member] |  |
Disaggregation Of Revenue [Line Items] |  |
Unbilled contract assets | $ 1.4 | $ 1.0

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