Investments (Tables)

3 Months Ended

Mar. 27, 2021

Investments, Debt and Equity Securities [Abstract]

Available For Sale Debt Securities [Table Text Block]

Following is a summary of debt securities as of March 27, 2021 and December 26, 2020:

	Cost		Gross Unrealized Gains	Gross Unrealized Losses	Fair Value
	(Amounts are in thousands)
March 27, 2021
Tax exempt bonds	$	494,115	5,776	47	499,844
Taxable bonds	8,315,795		194,900	59,194	8,451,501
Restricted investments	167,840		12,367	—	180,207
	$	8,977,750	213,043	59,241	9,131,552
December 26, 2020
Tax exempt bonds	$	548,438	7,408	88	555,758
Taxable bonds	8,182,003		286,745	8,324	8,460,424
Restricted investments	167,727		14,383	—	182,110
	$	8,898,168	308,536	8,412	9,198,292

Amortized Cost and Fair Value of Available For Sale Debt Securities by Expected Maturity [Table Text Block]

The cost and fair value of debt securities by expected maturity as of March 27, 2021 and December 26, 2020 are as follows:

			March 27, 2021			December 26, 2020
	Cost			Fair Value	Cost		Fair Value
	(Amounts are in thousands)
Due in one year or less	$	657,850		661,992	677,453		682,965
Due after one year through five years	5,551,701			5,705,691	5,330,696		5,533,074
Due after five years through ten years	2,764,758			2,760,188	2,886,333		2,978,301
Due after ten years	3,441			3,681	3,686		3,952
	$	8,977,750		9,131,552	8,898,168		9,198,292

Available For Sale Debt Securities in an Unrealized Loss Position by Time Period Impaired [Table Text Block]

Following is a summary of debt securities with other unrealized losses by the time period impaired as of March 27, 2021 and December 26, 2020:

			Less Than 12 Months				12 Months or Longer				Total
	Fair Value			Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
	(Amounts are in thousands)
March 27, 2021
Tax exempt bonds	$	9,961			47	—			—	9,961			47
Taxable bonds	2,963,006				58,823	39,629			371	3,002,635			59,194
	$	2,972,967			58,870	39,629			371	3,012,596			59,241
December 26, 2020
Tax exempt bonds	$	3,704			88	—			—	3,704			88
Taxable bonds	1,157,387				7,946	39,622			378	1,197,009			8,324
	$	1,161,091			8,034	39,622			378	1,200,713			8,412

Investment Income (Loss) [Table Text Block]

Following is a summary of investment income (loss) for the three months ended March 27, 2021 and March 28, 2020:

		Three Months Ended
	March 27, 2021			March 28, 2020
	(Amounts are in thousands)
Interest and dividend income		$	48,670		54,268
Net realized gain on investments		7,489			2,314
		56,159			56,582
Fair value adjustment, due to net unrealized gain (loss), on equity securities held at end of period		784,850			(387,427)
		$	841,009		(330,845)