Employee Benefit Plans - Description of Investment Policy (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Defined Benefit Plan Disclosure
Projected benefit obligation	$ 138,412	$ 126,227	$ 144,939
Accumulated benefit obligation	138,412	126,227
Fair value of plan assets at measurement date	$ 79,819	$ 79,189	104,559
Plan assets by category	100.00%	100.00%
Equity Securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 52,316	$ 50,904
Plan assets by category	66.00%	64.00%
Debt securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 22,550	$ 23,561
Plan assets by category	28.00%	30.00%
Real estate
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 4,953	$ 4,724
Plan assets by category	6.00%	6.00%
Brewmatic Plan
Defined Benefit Plan Disclosure
Projected benefit obligation	$ 133,326	$ 121,752	3,724
Accumulated benefit obligation	133,326	121,752
Fair value of plan assets at measurement date	$ 75,904	$ 75,411	3,719
Plan assets by category	100.00%	100.00%
Brewmatic Plan \| Equity Securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 49,744	$ 48,464
Plan assets by category	66.00%	64.00%
Brewmatic Plan \| Debt securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 21,439	$ 22,461
Plan assets by category	28.00%	30.00%
Brewmatic Plan \| Real estate
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 4,721	$ 4,486
Plan assets by category	6.00%	6.00%
Hourly Employees’ Plan
Defined Benefit Plan Disclosure
Projected benefit obligation	$ 5,086	$ 4,475	4,040
Accumulated benefit obligation	5,086	4,475
Fair value of plan assets at measurement date	$ 3,915	$ 3,778	$ 3,629
Plan assets by category	100.00%	100.00%
Hourly Employees’ Plan \| Equity Securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 2,572	$ 2,440
Plan assets by category	66.00%	65.00%
Hourly Employees’ Plan \| Debt securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 1,111	$ 1,100
Plan assets by category	28.00%	29.00%
Hourly Employees’ Plan \| Real estate
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 232	$ 238
Plan assets by category	6.00%	6.00%

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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