Investments (Tables)

12 Months Ended

Dec. 27, 2014

Investments, Debt and Equity Securities [Abstract]

Available For Sale Securities

Following is a summary of AFS securities as of December 27, 2014 and December 28, 2013:

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
	(Amounts are in thousands)
2014
Tax exempt bonds	$	3,205,647		17,460		4,011	3,219,096
Taxable bonds	1,569,828			3,005		4,592	1,568,241
Restricted investments	170,000			—		776	169,224
Equity securities	1,092,985			191,493		10,309	1,274,169
	$	6,038,460		211,958		19,688	6,230,730
2013
Tax exempt bonds	$	3,430,028		25,588		9,917	3,445,699
Taxable bonds	1,445,901			7,641		3,863	1,449,679
Restricted investments	170,000			—		86	169,914
Equity securities	790,975			139,119		3,900	926,194
	$	5,836,904		172,348		17,766	5,991,486

Amortized Cost and Fair Value of Available for Sale Securities by Expected Maturity

The amortized cost and fair value of AFS securities by expected maturity as of December 27, 2014 and December 28, 2013 are as follows:

	2014			2013
	Amortized Cost		Fair Value	Amortized Cost	Fair Value
			(Amounts are in thousands)
Due in one year or less	$	996,674	999,169	824,780	829,559
Due after one year through five years	3,493,708		3,501,821	3,590,615	3,609,115
Due after five years through ten years	183,552		183,168	295,407	288,421
Due after ten years	101,541		103,179	165,127	168,283
	4,775,475		4,787,337	4,875,929	4,895,378
Restricted investments	170,000		169,224	170,000	169,914
Equity securities	1,092,985		1,274,169	790,975	926,194
	$	6,038,460	6,230,730	5,836,904	5,991,486

Temporarily Impaired Available for Sale Securities by Time Period Impaired

Following is a summary of temporarily impaired AFS securities by the time period impaired as of December 27, 2014 and December 28, 2013:

	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)
2014
Tax exempt bonds	$	689,909		2,359	93,454		1,652	783,363		4,011
Taxable bonds	936,512			3,666	68,035		926	1,004,547		4,592
Restricted investments	169,224			776	—		—	169,224		776
Equity securities	107,352			8,373	6,229		1,936	113,581		10,309
Total temporarily impaired AFS securities	$	1,902,997		15,174	167,718		4,514	2,070,715		19,688
2013
Tax exempt bonds	$	502,304		6,710	106,985		3,207	609,289		9,917
Taxable bonds	535,233			3,347	19,367		516	554,600		3,863
Restricted investments	169,914			86	—		—	169,914		86
Equity securities	31,400			3,499	3,152		401	34,552		3,900
Total temporarily impaired AFS securities	$	1,238,851		13,642	129,504		4,124	1,368,355		17,766