Schedule of Fair Value of Assets and Liabilities (Detail) - USD ($) $ in Millions	Mar. 26, 2022	Dec. 25, 2021
Carrying Amount
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Company-owned life insurance	$ 136	$ 137
Carrying Amount | Long-Term Debt | New Facilities loans Under Third Amended Credit Agreement due 2025
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt, fair value	57	100
Fair Value
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Company-owned life insurance	136	137
Fair Value | Long-Term Debt | New Facilities loans Under Third Amended Credit Agreement due 2025
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt, fair value	57	100
Revenue bonds, due in varying amounts periodically through 2029 | Carrying Amount | Long-Term Debt
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt, fair value	75	75
Revenue bonds, due in varying amounts periodically through 2029 | Fair Value | Long-Term Debt
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt, fair value	76	76
American & Foreign Power Company, Inc. 5% debentures, due 2030 | Carrying Amount | Long-Term Debt
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt, fair value	15	15
American & Foreign Power Company, Inc. 5% debentures, due 2030 | Fair Value | Long-Term Debt
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Long-term debt, fair value	$ 15	$ 16