Employee Benefit Plans - Description of Investment Policy (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Defined Benefit Plan Disclosure
Projected benefit obligation	$ 126,227	$ 144,939	$ 154,699
Accumulated benefit obligation	126,227	144,939
Fair value of plan assets at measurement date	$ 79,189	$ 104,559	103,418
Plan assets by category	100.00%	100.00%
Equity Securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 50,904	$ 68,319
Plan assets by category	64.00%	65.00%
Debt securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 23,561	$ 29,729
Plan assets by category	30.00%	29.00%
Real estate
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 4,724	$ 6,511
Plan assets by category	6.00%	6.00%
Farmer Brothers Plan
Defined Benefit Plan Disclosure
Projected benefit obligation	$ 0	$ 137,175	146,291
Accumulated benefit obligation	0	137,175
Fair value of plan assets at measurement date	$ 0	$ 97,211	97,304
Plan assets by category	0.00%	100.00%
Farmer Brothers Plan \| Equity Securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 0	$ 63,547
Plan assets by category	0.00%	66.00%
Farmer Brothers Plan \| Debt securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 0	$ 27,608
Plan assets by category	0.00%	28.00%
Farmer Brothers Plan \| Real estate
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 0	$ 6,056
Plan assets by category	0.00%	6.00%
Brewmatic Plan
Defined Benefit Plan Disclosure
Projected benefit obligation	$ 121,752	$ 3,724	4,079
Accumulated benefit obligation	121,752	3,724
Fair value of plan assets at measurement date	$ 75,411	$ 3,719	3,115
Plan assets by category	100.00%	100.00%
Brewmatic Plan \| Equity Securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 48,464	$ 2,431
Plan assets by category	64.00%	66.00%
Brewmatic Plan \| Debt securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 22,461	$ 1,056
Plan assets by category	30.00%	28.00%
Brewmatic Plan \| Real estate
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 4,486	$ 232
Plan assets by category	6.00%	6.00%
Hourly Employees’ Plan
Defined Benefit Plan Disclosure
Projected benefit obligation	$ 4,475	$ 4,040	4,329
Accumulated benefit obligation	4,475	4,040
Fair value of plan assets at measurement date	$ 3,778	$ 3,629	$ 2,999
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	$ 2,440	$ 2,341
Plan assets by category	65.00%	65.00%
Hourly Employees’ Plan \| Debt securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 1,100	$ 1,065
Plan assets by category	29.00%	29.00%
Hourly Employees’ Plan \| Real estate
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 238	$ 223
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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