Financial Instruments, Fair Value, and Concentrations of Credit Risk - Additional Information (Detail) - USD ($) $ in Millions |
Mar. 31, 2019 |
Dec. 31, 2018 |
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| Fair Value, Concentration of Risk, Financial Assets, Balance Sheet Groupings [Abstract] | ||
| Fair value of financing leases | $ 15.6 | $ 15.8 |
| Financing lease obligations | $ 18.4 | $ 18.5 |
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- Definition Capital Lease Obligations Fair Value Disclosure No definition available.
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- References No definition available.
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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