Employee Benefit Plans - Obligations and Funded Status (Details) - USD ($) $ in Thousands	12 Months Ended
May 31, 2018	May 31, 2017
Change in benefit obligation:
Projected benefit obligation, beginning of year	$ 87,387	$ 0
Projected benefit obligation acquired in G&K acquisition	0	84,553
Interest cost	2,818	562
Actuarial (gain) loss	(940)	2,750
Benefits paid	(2,924)	(478)
Projected benefit obligation, end of year	86,341	87,387
Change in plan assets:
Fair value of plan assets, beginning of year	59,396	0
Plan assets acquired in G&K acquisition	0	57,747
Actual return on plan assets	2,309	2,127
Benefits paid	(2,924)	(478)
Fair value of plan assets, end of year	58,781	59,396
Funded status-net amount recognized	$ (27,560)	$ (27,991)

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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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 payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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- Definition

Amount of increase in benefit obligation of defined benefit plan from business combination.

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Amount of increase in plan assets of defined benefit plan from business combination.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

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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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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