Defined Benefit Plans, Service Period, Years Eligible for Benefits Calculation

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- Definition

Defined Benefit Plans, Service Period for Determining Benefits

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For those employees who are not covered by a defined benefit plan, the percentage of their gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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- Definition

The maximum percentage of annual postretirement medical plan cost increase that is to be paid by the employer.

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

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year.

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- Definition

Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status.

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- Definition

Percentage of target 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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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

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- Definition

Amount of (increase) decrease to benefit obligation of defined benefit plan from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Includes, but is not limited to, lump-sum cash payment to participant in exchange for right to receive specified benefits, purchase of nonparticipating annuity contract and change from remeasurement.

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- Definition

Ultimate trend rate for health care cost for defined benefit postretirement plan.

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- Definition

Year ultimate health care cost trend rate is expected to be reached, in YYYY format.

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- Definition

Amount of cost for defined contribution plan.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Percentage employer matches of the employee's percentage contribution matched.

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- Definition

States the frequency (for example, annually, semi-annually, quarterly) with which the entity can redeem its investment, or portion thereof, for each of those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments), by major category.

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Notice period the entity is required to deliver before it can redeem an investment calculated using net asset value per share, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, investments calculated by per unit, per membership interest, other equity or ownership interest and alternative investments.

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The amount of unfunded commitments for which the entity is obligated, to those certain investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure) (alternative investments).

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- Definition

Amount of cost (reversal of cost) for pension and other postretirement benefits.

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Retirement Benefits (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2022	Dec. 31, 2021	Dec. 25, 2020
Defined Contribution Plan
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	100.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	3.00%
Company contribution rate for employees not covered by DBP	2.00%
Company contributions to 401K	$ 11,000	$ 10,000	$ 8,700
Defined Benefit Plan Disclosure [Line Items]
Highest earnings years	5 years
Years preceding retirement	10 years
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 20,000	20,000
Accumulated benefit obligation for all defined benefit plans	297,000	388,000
Pension and Other Postretirement Benefits Cost (Reversal of Cost)	$ 1,000	12,000	5,000
Pension Plan - Blue Plan [Member] \| Equity
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations	53.00%
Pension Plan - Blue Plan [Member] \| Fixed income
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations	42.00%
Pension Plan - Blue Plan [Member] \| Real Estate and Other
Defined Benefit Plan Disclosure [Line Items]
Target plan asset allocations	5.00%
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	$ 0	64,886
Settlement loss (gain)	$ 0	12,285	0
Investments at Net Asset Value, Redemption Frequency	daily
Investments at Net Asset Value, Unfunded Commitments	$ 2,300	2,400
Defined Benefit Plan, Plan Assets, Contributions by Employer	22,756	22,493
Expected company contributions to retirement plans next year	1,900
Pension Benefits \| Pension Plan - Blue and Gray Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement		63,000
Settlement loss (gain)		(12,000)
Postretirement Medical Benefits
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	0	0
Settlement loss (gain)	0	0	$ 0
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 1,503	$ 1,447
Retirement medical plan limit on annual increase in company cost	3.00%
Expected company contributions to retirement plans next year	$ 1,800
Assumed health care trend rates
Health care cost trend rate assumed for next year	8.50%
Ultimate health care cost trend rate	4.50%
Year that rate reaches ultimate trend rate	2038
Minimum \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Investments at Net Asset Value, Redemption Notice Period	10 days
Maximum \| Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Investments at Net Asset Value, Redemption Notice Period	60 days