Pension Benefits and Other Postretirement Benefits (Additional Information) (Details)		2 Months Ended		3 Months Ended				12 Months Ended
	Oct. 17, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($) plan
Defined Benefit Plan Disclosure [Line Items]
Number of qualified noncontributory defined benefit plans | plan								2
Pension assets		$ 12,790,000	$ 12,790,000		$ 12,954,000	$ 12,790,000		$ 12,790,000
Voluntary contributions					0		$ 0
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Payment for settlement	$ 123,500,000	$ 1,300,000
Lump sum distributions			$ 38,900,000
Pension assets					$ 9,000,000.0
Settlement charge						$ (53,200,000)
Pension Benefits | Forecast
Defined Benefit Plan Disclosure [Line Items]
Expected future settlement charges				$ 700,000