Investments (Tables)

9 Months Ended

Sep. 29, 2018

Investments, Debt and Equity Securities [Abstract]

Available For Sale Debt Securities [Table Text Block]

Following is a summary of debt securities as of September 29, 2018 and December 30, 2017:

	Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
	(Amounts are in thousands)
September 29, 2018
Tax exempt bonds	$	1,340,795		110		20,347	1,320,558
Taxable bonds	2,406,444			340		58,739	2,348,045
	$	3,747,239		450		79,086	3,668,603
December 30, 2017
Tax exempt bonds	$	1,811,523		602		16,420	1,795,705
Taxable bonds	2,115,174			695		25,443	2,090,426
	$	3,926,697		1,297		41,863	3,886,131

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 September 29, 2018 and December 30, 2017 are as follows:

	September 29, 2018			December 30, 2017
	Cost		Fair Value	Cost	Fair Value
	(Amounts are in thousands)
Due in one year or less	$	577,480	575,195	917,576	915,579
Due after one year through five years	2,713,698		2,640,263	2,794,099	2,757,504
Due after five years through ten years	448,838		445,862	205,792	203,533
Due after ten years	7,223		7,283	9,230	9,515
	$	3,747,239	3,668,603	3,926,697	3,886,131

Temporarily Impaired Available For Sale Debt Securities by Time Period Impaired [Table Text Block]

Following is a summary of temporarily impaired debt securities by the time period impaired as of September 29, 2018 and December 30, 2017:

	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)
September 29, 2018
Tax exempt bonds	$	775,195		8,384	537,591		11,963	1,312,786		20,347
Taxable bonds	1,214,748			20,329	1,017,301		38,410	2,232,049		58,739
	$	1,989,943		28,713	1,554,892		50,373	3,544,835		79,086
December 30, 2017
Tax exempt bonds	$	1,543,151		13,827	136,217		2,593	1,679,368		16,420
Taxable bonds	811,886			4,908	1,153,645		20,535	1,965,531		25,443
	$	2,355,037		18,735	1,289,862		23,128	3,644,899		41,863

Equity Securities [Table Text Block]

Following is a summary of the fair value of equity securities as of September 29, 2018 and December 30, 2017:

	September 29, 2018			December 30, 2017
	(Amounts are in thousands)
Equity securities		$	3,023,603		2,383,095
Restricted investment		161,307			164,085
		$	3,184,910		2,547,180

Investment Income [Table Text Block]

Following is a summary of investment income for the three and nine months ended September 29, 2018 and September 30, 2017:

		Three Months Ended						Nine Months Ended
	September 29, 2018				September 30, 2017		September 29, 2018			September 30, 2017
	(Amounts are in thousands)
Interest income		$	21,822			16,984		60,077			59,031
Dividend income		10,904				11,123		32,802			28,994
Net realized gain on sale of investments		69,251				10,323		92,918			104,881
		101,977				38,430		185,797			192,906
Fair value adjustment (net unrealized gain) on equity securities held at end of period		166,267				—		217,314			—
Net gain on sale of equity securities previously recognized through fair value adjustment		(38,010		)		—		(60,424	)		—
		$	230,234			38,430		342,687			192,906