Employee Benefit Plans - Narrative (Details) $ in Thousands		3 Months Ended			6 Months Ended	9 Months Ended
	Mar. 23, 2020 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Mar. 31, 2020 USD ($) shares	Dec. 31, 2020 USD ($)	Mar. 31, 2021 USD ($) plan shares	Mar. 31, 2020 USD ($) shares
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Contribution Plan, Employer Matching Contribution, Amount				$ 500
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Reclassification Adjustment, before Tax	$ (13,400)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Increase (Decrease) for Plan Amendment	$ (14,600)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Curtailment					$ (5,800)
Amortization expense		$ 600	$ 600			$ 1,800
Other Postretirement Benefit Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Multiemployer plans, number of plans | plan						9
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Curtailment		$ 0		$ (5,750)		$ 0	$ (5,750)
Restated and Amended 401K Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined contribution plan, employer matching contribution, percent of eligible income						4.00%
Defined Contribution Plan, Number of Shares Contributed | shares				104,247		322,100	213,896
Defined Contribution Plan, Employer Discretionary Contribution Amount				$ 900		$ 1,800	$ 2,300
Defined Benefit Plan, Plan Assets, Contributions by Employer						$ 1,900