CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 28, 2015	Mar. 29, 2014
Statement of Comprehensive Income [Abstract]
Unrealized (loss) gain on available-for-sale (AFS) securities, tax effect	$ (2,022)	$ 7,502
Reclassification adjustment for net realized gain on AFS securities, tax effect	(5,941)	(2,165)
Adjustment to postretirement benefit plan obligation, tax effect	$ 91	$ 53

Amount of tax (expense) benefit, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e640-108580

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-Name Accounting Standards Codification

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e640-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

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-Section 45

-Paragraph 10A

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-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580

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