Employee Benefit Plans - Description of Investment Policy (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Farmer Brothers Plan
Defined Benefit Plan Disclosure
Projected benefit obligation	$ 137,175	$ 146,291	$ 152,325
Accumulated benefit obligation	137,175	146,291
Fair value of plan assets at measurement date	$ 97,211	$ 97,304	91,201
Plan assets by category	0.00%	0.00%
Farmer Brothers Plan \| Equity Securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 63,547	$ 65,270
Plan assets by category	66.00%	67.00%
Farmer Brothers Plan \| Debt securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 27,608	$ 26,241
Plan assets by category	28.00%	27.00%
Farmer Brothers Plan \| Real estate
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 6,056	$ 5,793
Plan assets by category	6.00%	6.00%
Brewmatic Plan
Defined Benefit Plan Disclosure
Projected benefit obligation	$ 3,724	$ 4,079	4,574
Accumulated benefit obligation	3,724	4,079
Fair value of plan assets at measurement date	$ 3,719	$ 3,115	2,989
Plan assets by category	100.00%	100.00%
Brewmatic Plan \| Equity Securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 2,431	$ 2,133
Plan assets by category	66.00%	69.00%
Brewmatic Plan \| Debt securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 1,056	$ 793
Plan assets by category	28.00%	25.00%
Brewmatic Plan \| Real estate
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 232	$ 189
Plan assets by category	6.00%	6.00%
Hourly Employees’ Plan
Defined Benefit Plan Disclosure
Projected benefit obligation	$ 4,040	$ 4,329	4,329
Accumulated benefit obligation	4,040	4,329
Fair value of plan assets at measurement date	$ 3,629	$ 2,999	$ 2,447
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	$ 2,341	$ 1,973
Plan assets by category	65.00%	66.00%
Hourly Employees’ Plan \| Debt securities
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 1,065	$ 851
Plan assets by category	29.00%	28.00%
Hourly Employees’ Plan \| Real estate
Defined Benefit Plan Disclosure
Fair value of plan assets at measurement date	$ 223	$ 175
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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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+ References

No definition available.

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- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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