Retirement Plan - Schedule of Net Periodic Benefit Cost (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Dec. 26, 2019	Dec. 27, 2018	Dec. 26, 2019	Dec. 27, 2018
Retirement Benefits [Abstract]
Service cost	$ 178	$ 153	$ 356	$ 305
Interest cost	223	223	446	447
Amortization of loss	104	23	208	47
Amortization of prior service cost	240	240	479	479
Net periodic benefit cost	$ 745	$ 639	$ 1,489	$ 1,278

No definition available.

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Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan.

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Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan.

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

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Amount of net periodic benefit cost (credit) for defined benefit plan.

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

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