Fair Value of Financial Instruments (Details Textual) - USD ($) |
3 Months Ended | 9 Months Ended | |
|---|---|---|---|
Sep. 26, 2015 |
Sep. 26, 2015 |
Sep. 27, 2014 |
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| Fair Value of Financial Instruments (Textual) [Abstract] | |||
| Securities held with stated maturities | 12 months | ||
| Securities classifies as current assets under caption marketable securities maturities | 12 months | ||
| Realized loss on available for sale securities | $ 241,000 | $ 180,000 | |
| Other than Temporary Impairment Losses, Investments | $ 0 | ||
| Nonrecurring [Member] | |||
| Fair Value of Financial Instruments (Textual) [Abstract] | |||
| Fair value adjustments for assets measured at fair value | 0 | ||
| Fair value adjustments for liabilities measured at fair value | $ 0 | ||
| Phantom Share Units (PSUs) [Member] | |||
| Fair Value of Financial Instruments (Textual) [Abstract] | |||
| Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period | 3 years | ||
| Recognized expense related to deferred director stock units and phantom stock units liability | $ 10,000 | $ 26,000 | |
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- Definition Fair value liability recorded for share based awards related expense. No definition available.
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- Definition Fair value of financial instruments. No definition available.
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- Definition Securities classifies as current assets under caption marketable securities maturities. No definition available.
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- Definition Securities Held With Stated Maturities Period. No definition available.
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- Definition Amount of addition (reduction) to the amount at which an asset could be incurred (settled) in a current transaction between willing parties. No definition available.
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- Definition This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties. No definition available.
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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