Post Retirement Benefits (Details) - USD ($)	3 Months Ended		6 Months Ended		9 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2020
Pension, health and life insurance expense:
Multiemployer Plan, Employer Contribution, Cost	$ 145,000	$ 231,000	$ 391,000	$ 462,000
Defined contribution plan contributions	215,000	324,000	508,000	586,000
Total pension expense	360,000	555,000	899,000	1,048,000
Interest cost	59,000	72,000	118,000	144,000
Amortization of prior service costs	(124,000)	(125,000)	(248,000)	(250,000)
Amortization of net loss	45,000	29,000	90,000	58,000
Net periodic benefit cost	(20,000)	(24,000)	(40,000)	(48,000)
Total post retirement benefits expense	340,000	$ 531,000	859,000	$ 1,000,000
Payments to pension plans			511,000
Payments for post retirement healthcare and life insurance			91,000
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accrued Expected Pension Plan Payments	$ 839,000		$ 839,000
Forecast [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected payments to pension plans					$ 1,385,000
Expected future payments for other post retirement benefits					$ 1,142,000