EMPLOYEE BENEFITS (Details 5) (Pension plans, USD $) In Thousands, unless otherwise specified	Dec. 30, 2012	Dec. 25, 2011	Dec. 26, 2010
EMPLOYEE BENEFITS
Total	$ 1,352,711	$ 1,255,822
Pending trades	6,166	(22,516)
Fair value of plan assets	1,358,877	1,233,306	1,051,410
Cash and cash equivalents
EMPLOYEE BENEFITS
Total	1,161	30,816
Mutual funds
EMPLOYEE BENEFITS
Total	257,398	40,861
Corporate stock
EMPLOYEE BENEFITS
Total		211
Corporate debt instruments
EMPLOYEE BENEFITS
Total	98	86,776
U.S. Government securities
EMPLOYEE BENEFITS
Total	107,337	236,063
Common collective trusts
EMPLOYEE BENEFITS
Total	928,730	764,983
Mortgage and asset backed securities
EMPLOYEE BENEFITS
Total		22,265
Real Estate
EMPLOYEE BENEFITS
Total	51,579	50,530
Other
EMPLOYEE BENEFITS
Total	6,408	23,317
Level 1
EMPLOYEE BENEFITS
Total	258,559	71,888
Level 1 | Cash and cash equivalents
EMPLOYEE BENEFITS
Total	1,161	30,816
Level 1 | Mutual funds
EMPLOYEE BENEFITS
Total	257,398	40,861
Level 1 | Corporate stock
EMPLOYEE BENEFITS
Total		211
Level 2
EMPLOYEE BENEFITS
Total	1,036,165	1,124,505
Level 2 | Corporate debt instruments
EMPLOYEE BENEFITS
Total	98	86,776
Level 2 | U.S. Government securities
EMPLOYEE BENEFITS
Total	107,337	236,063
Level 2 | Common collective trusts
EMPLOYEE BENEFITS
Total	928,730	764,983
Level 2 | Mortgage and asset backed securities
EMPLOYEE BENEFITS
Total		22,265
Level 2 | Other
EMPLOYEE BENEFITS
Total		14,418
Level 3
EMPLOYEE BENEFITS
Total	57,987	59,429	36,728
Level 3 | Real Estate
EMPLOYEE BENEFITS
Total	51,579	50,530
Level 3 | Other
EMPLOYEE BENEFITS
Total	$ 6,408	$ 8,899