Segment Information (Information Regarding Reportable Business) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 24, 2011 Cus	Sep. 25, 2010 Cus	Sep. 24, 2011 Cus	Sep. 25, 2010 Cus	Dec. 25, 2010
External revenue	$ 684,013	$ 622,826	$ 1,931,560	$ 1,812,635
Investment income	373	495	1,294	1,069
Internal revenue	5,864	5,902	21,681	21,463
Operating income	49,533	35,886	132,295	104,163
Expenditures on long-lived assets	631	790	3,460	25,474
Goodwill	57,470	57,470	57,470	57,470	57,470
Number of customers accounting for 10 percent or more of total revenue	0	0	0	1
Percentage of one customer for company's revenue				11.00%
Transportation Logistics [Member]
External revenue	675,416	614,273	1,906,037	1,787,107
Operating income	41,254	31,108	113,749	88,460
Expenditures on long-lived assets	631	790	3,460	25,474
Goodwill	57,470	57,470	57,470	57,470
Insurance [Member]
External revenue	8,597	8,553	25,523	25,528
Investment income	373	495	1,294	1,069
Internal revenue	5,864	5,902	21,681	21,463
Operating income	$ 8,279	$ 4,778	$ 18,546	$ 15,703

Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details