EMPLOYEE BENEFITS (Details 5) (Pension plans, USD $) In Thousands, unless otherwise specified	Dec. 29, 2013	Dec. 30, 2012	Dec. 25, 2011
EMPLOYEE BENEFITS
Total	$ 1,426,678	$ 1,352,711
Pending trades	6,017	6,166
Fair value of plan assets	1,432,695	1,358,877	1,233,305
Cash and cash equivalents
EMPLOYEE BENEFITS
Total	844	1,161
Mutual funds
EMPLOYEE BENEFITS
Total	273,450	257,398
Corporate debt instruments
EMPLOYEE BENEFITS
Total	105	98
U.S. Government securities
EMPLOYEE BENEFITS
Total	112,530	107,337
Common collective trusts
EMPLOYEE BENEFITS
Total	980,317	928,730
Real Estate
EMPLOYEE BENEFITS
Total	52,265	51,579
Other
EMPLOYEE BENEFITS
Total	7,167	6,408
Level 1
EMPLOYEE BENEFITS
Total	274,294	258,559
Level 1 | Cash and cash equivalents
EMPLOYEE BENEFITS
Total	844	1,161
Level 1 | Mutual funds
EMPLOYEE BENEFITS
Total	273,450	257,398
Level 2
EMPLOYEE BENEFITS
Total	1,092,952	1,036,165
Level 2 | Corporate debt instruments
EMPLOYEE BENEFITS
Total	105	98
Level 2 | U.S. Government securities
EMPLOYEE BENEFITS
Total	112,530	107,337
Level 2 | Common collective trusts
EMPLOYEE BENEFITS
Total	980,317	928,730
Level 3
EMPLOYEE BENEFITS
Total	59,432	57,987	59,429
Level 3 | Real Estate
EMPLOYEE BENEFITS
Total	52,265	51,579	50,530
Level 3 | Other
EMPLOYEE BENEFITS
Total	$ 7,167	$ 6,408