Consolidated Statements of Comprehensive Earnings (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 30, 2023	Dec. 31, 2022	Dec. 25, 2021
Statement of Comprehensive Income [Abstract]
Unrealized gain (loss) on debt securities net of income taxes	$ 70,000	$ (214,000)	$ (68,000)
Reclassification adjustment for net realized loss (gain) on debt securities net of income taxes	0	1,000	(5,000)
Adjustment to postretirement benefit obligation net of income taxes	$ (400)	$ 7,000	$ 3,000

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

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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.

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Amount, before adjustment, of tax expense (benefit) for unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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-Paragraph 12
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