The defined benefit plan decrease in assumed healthcare cost trend rate percentage.

No definition available.

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- Definition

The total amount of net periodic benefit income for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

+ References

No definition available.

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- Definition

Percentage of the Fair Value to Determine the price of common stock.

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Share based compensation arrangement by share based payment award percentage of shares available for issue.

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No definition available.

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- Definition

stock issued during period shares employee stock purchase plans future issuance.

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No definition available.

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- Definition

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 1
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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable within one year (or the operating cycle, if longer). Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

+ References

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- Definition

After tax net amount of gain (loss) that are not yet recognized as a component of net periodic benefit cost, and that are recognized as increases (decreases) in other comprehensive income as they arise.

+ References

No definition available.

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- Definition

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

+ References

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- Definition

Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

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Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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Target allocation of investments of this type to total plan assets presented on a weighted average basis.

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- Definition

The ultimate trend rate for health care costs.

+ References

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

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

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No definition available.

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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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No definition available.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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No definition available.

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Unrecognized cost of unvested options awarded to employees as compensation.

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No definition available.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of additional shares authorized for issuance under an established share-based compensation plan.

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No definition available.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

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Percentage of vesting of share-based compensation awards.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Note 6 - Employee Benefit Plans (Details Textual) - USD ($)		12 Months Ended
	May. 12, 2015	Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013	Dec. 31, 2015	Dec. 31, 2014
Swiss Plan [Member]
Defined Benefit Plan, Accumulated Other Comprehensive Income Net Gains (Losses), after Tax		$ (1,800,000)	$ (2,000,000)
Defined Benefit Plans, Estimated Future Employer Contributions in Next Fiscal Year		700,000
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months		600,000
Defined Benefit Plan, Expected Future Benefit Payments, Year Two		600,000
Defined Benefit Plan, Expected Future Benefit Payments, Year Three		700,000
Defined Benefit Plan, Expected Future Benefit Payments, Year Four		800,000
Defined Benefit Plan, Expected Future Benefit Payments, Year Five		900,000
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter		5,200,000
Defined Benefit Plan, Net Periodic Benefit Cost		$ 1,209,000	$ 897,000	$ 972,000
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate					1.00%	1.30%
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	750,000
Stock Issued During Period Shares Employee Stock Purchase Plans Future Issuance		2,650,000
Percentage of Fair Value to Determine Price of Common Stock		85.00%
Stock Issued During Period, Shares, Employee Stock Purchase Plans		122,528	138,831	163,120
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		811,063
Equity Incentive Plan 2005 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	1,500,000
Percentage of Fair Value to Determine Price of Common Stock		100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		2,255,701
Debt Securities [Member]
Defined Benefit Plan, Target Plan Asset Allocations		75.00%
Real Estate Investments [Member]
Defined Benefit Plan, Target Plan Asset Allocations		12.00%
Alternative Investments [Member]
Defined Benefit Plan, Target Plan Asset Allocations		8.00%
Cash [Member]
Defined Benefit Plan, Target Plan Asset Allocations		2.00%
Equity Securities [Member]
Defined Benefit Plan, Target Plan Asset Allocations		3.00%
Post-retirement Health benefits [Member]
Defined Benefit Plans, Estimated Future Employer Contributions in Next Fiscal Year		$ 100,000
Defined Benefit Plan, Expected Future Benefit Payments, Next Twelve Months		100,000
Defined Benefit Plan, Expected Future Benefit Payments, Year Two		100,000
Defined Benefit Plan, Expected Future Benefit Payments, Year Three		100,000
Defined Benefit Plan, Expected Future Benefit Payments, Year Four		100,000
Defined Benefit Plan, Expected Future Benefit Payments, Year Five		100,000
Defined Benefit Plan, Expected Future Benefit Payments, Five Fiscal Years Thereafter		700,000
Defined Benefit Plan, Net Periodic Benefit Cost		$ 100,000		$ 100,000
Defined Benefit Plan, Net Periodic Benefit Income			$ 100,000
Employee Stock Option [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		1 year
Employee Stock Option [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		4 years
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		10 years
Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		1 year
Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		4 years
Equity Based Performance Stock Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Shares Available for Issue		0.00%
Equity Based Performance Stock Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Shares Available for Issue		150.00%
Equity Based Performance Stock Units [Member] \| Vest on Second and Third Anniversary Grant Date [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage			50.00%
Equity Based Performance Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		3 years
Unvested Stock Options [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options		$ 600,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition		1 year 73 days
Unvested Restricted Stock Units [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition		2 years 109 days
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options		$ 10,000,000
Deferred Compensation Liability, Current		2,600,000	$ 2,600,000
Cash Surrender Value of Life Insurance		2,300,000	$ 2,300,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value		1,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value		1,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value		$ 1,200,000
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay		3.00%	3.00%	1.50%
Defined Contribution Plan, Employer Discretionary Contribution Amount		$ 700,000	$ 700,000	$ 300,000
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate		4.20%	3.80%	4.60%
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year		7.50%
Defined Benefit Plan Decrease In Assumed Healthcare Cost Trend Rate Percentage		0.30%
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate		4.50%
Defined Benefit Plan, Year that Rate Reaches Ultimate Trend Rate		2025
Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components		$ 14,000
Defined Benefit Plan, Effect of One Percentage Point Decrease on Service and Interest Cost Components		11,000
Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation		411,000
Defined Benefit Plan, Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation		338,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value		$ 700,000	$ 700,000	$ 400,000