Postretirement Benefits Schedule of Net Funded Status and APBO (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Jan. 01, 2017	Jan. 03, 2016
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Benefit obligation at beginning of year	$ 4,566	$ 3,060
Service cost	192	150	$ 127
Interest cost	191	165	114
Plan participants' contributions	88	98
Actuarial loss (gain)	(122)	1,251
Benefits paid	(115)	(164)
Medicare part D prescription drug subsidy	38	6
Benefit obligation at end of year	4,838	4,566	3,060
Fair value of plan assets at beginning of year	0	0
Employer contributions	(11)	60
Funded status	(4,838)	(4,566)
Fair value of plan assets at end of year	$ 0	$ 0	$ 0
Discount rate used to determine benefit obligations	3.60%	4.11%
Discount rate used to determine net periodic benefit cost	4.11%	4.25%

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- Definition

Amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover, salary, and temporary deviation from the substantive plan.

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-Publisher FASB
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The interest rate used to adjust for the time value of money for the plan.

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The interest rate used to adjust for the time value of money.

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

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Amount of contributions made by the employer to defined benefit plans.

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The amount of contributions made by plan participants. This item represents a periodic increase to the plan obligation and an increase to plan assets.

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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.

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The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total.

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Amount of the period's gross receipts received from the prescription drug subsidy, which is to be used in the roll forward of the accumulated postretirement benefit obligation of an applicable postretirement benefit plan.

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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