Available for Sale Debt Securities Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 26, 2022	Dec. 25, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 10,548,657	$ 10,084,360
Unrealized Gains	17,534	118,677
Unrealized Losses	511,532	109,265
Fair Value	10,054,659	10,093,772
Tax exempt bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	229,832	268,899
Unrealized Gains	151	2,351
Unrealized Losses	142	0
Fair Value	229,841	271,250
Taxable bonds [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	10,153,631	9,644,692
Unrealized Gains	14,721	108,697
Unrealized Losses	510,023	108,906
Fair Value	9,658,329	9,644,483
Restricted investments [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	165,194	170,769
Unrealized Gains	2,662	7,629
Unrealized Losses	1,367	359
Fair Value	$ 166,489	$ 178,039

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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