Accumulated Other Comprehensive Earnings (Losses) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Accumulated Other Comprehensive Earnings (Losses), Net of Tax [Roll Forward]
Balances at beginning of period	$ (5)	$ 201	$ 81
Unrealized (loss) gain on debt securities	(626)	(201)	139
Net realized loss (gain) on debt securities reclassified to investment income	1	(16)	(13)
Adjustment to postretirement benefit obligation	21	11	(6)
Net other comprehensive earnings (losses)	(604)	(206)	120
Balances at end of period	(609)	(5)	201
Investments
Accumulated Other Comprehensive Earnings (Losses), Net of Tax [Roll Forward]
Balances at beginning of period	7	224	98
Unrealized (loss) gain on debt securities	(626)	(201)	139
Net realized loss (gain) on debt securities reclassified to investment income	1	(16)	(13)
Net other comprehensive earnings (losses)	(625)	(217)	126
Balances at end of period	(618)	7	224
Postretirement Benefit
Accumulated Other Comprehensive Earnings (Losses), Net of Tax [Roll Forward]
Balances at beginning of period	(12)	(23)	(17)
Adjustment to postretirement benefit obligation	21	11	(6)
Net other comprehensive earnings (losses)	21	11	(6)
Balances at end of period	$ 9	$ (12)	$ (23)

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

Amount after tax and reclassification adjustments of other comprehensive income (loss).

+ References

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+ Details