Annual and transition report of foreign private issuers pursuant to Section 13 or 15(d)

Asbestos - Additional Information (Detail)

v3.20.1
Asbestos - Additional Information (Detail)
1 Months Ended 12 Months Ended
Dec. 31, 2017
USD ($)
Dec. 31, 2017
AUD ($)
Mar. 31, 2020
USD ($)
Mar. 31, 2019
USD ($)
Mar. 31, 2018
USD ($)
Mar. 31, 2020
AUD ($)
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]            
Asbestos adjustments $ 43,600,000 $ 56,800,000 $ 58,200,000 $ 22,000,000.0 $ 156,400,000  
Secured standby loan facility maximum borrowing capacity     197,700,000     $ 320,000,000.0
Loan facility, outstanding balance     $ 0      
Rate of interest of Benchmark Bonds (as percent)     6.00%      
Secured Standby Loan Facility Maturity Date     Nov. 01, 2030      
Maturity date of Benchmark Bonds     May 01, 2020