Represents the maturity period of the investments held by the entity.

No definition available.

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- Definition

Accumulated appreciation or loss, net of tax, in value of the total of available-for-sale securities at the end of an accounting period.

+ References

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Period Type:	instant

- Definition

Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
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-Paragraph 1
-Subparagraph (SX 210.5-02.12)
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- Definition

This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the cost method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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- Definition

This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

+ References

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Balance Type:	credit
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- Definition

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.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Balance held at close of period in number of shares.

+ References

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- Definition

Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale.

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- Definition

The cash inflow associated with the sale of equity securities classified as available-for-sale securities.

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Significant Accounting Policies (Details 2) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended	6 Months Ended
	Jun. 24, 2015	Jun. 30, 2015	Jun. 30, 2015	Dec. 31, 2014
Marketable and Non-Marketable Securities
Marketable securities		$ 184,200	$ 184,200
Net unrealized gains (losses) recorded in accumulated other comprehensive income (loss)		1,700	1,700	$ 103,900
Carrying value of investments under the cost method		177,300	177,300	$ 167,100
Gain on sale of investment			80,187
Other-than-temporary non-cash charges			$ 0
Available for sale securities
Marketable and Non-Marketable Securities
Number of shares owned	5,710
Proceeds received from the sale of investments	$ 454,000
Available for sale securities \| Securities in captive insurance subsidiary portfolio \| Minimum
Marketable and Non-Marketable Securities
Investment maturity period			1 year
Available for sale securities \| Securities in captive insurance subsidiary portfolio \| Maximum
Marketable and Non-Marketable Securities
Investment maturity period			10 years
Available for sale securities \| Other Income.
Marketable and Non-Marketable Securities
Gain on sale of investment		$ 80,200	$ 80,200