EMPLOYEE BENEFITS - Assumptions (Details) (USD $)	12 Months Ended			3 Months Ended	9 Months Ended
	Dec. 28, 2014	Dec. 29, 2013	Dec. 30, 2012	Dec. 30, 2012	Sep. 30, 2012
Pension plan
Weighted average assumptions used for valuing benefit obligations
Discount rate (as a percent)	4.24%	5.01%
Weighted average assumptions used in calculating expense
Expected long-term return on plan assets (as a percent)	8.00%	8.00%	8.25%
Discount rate (as a percent)	5.01%	4.17%	5.31%
Medical cost trend rates
Contribution	$ 25,000,000	$ 7,600,000	$ 40,000,000
Gain or loss recognized on the contribution of property	0
Financing obligation from contribution of real property	34,600,000
Expected benefit payments
2015	98,178,000
2016	100,455,000
2017	104,703,000
2018	107,539,000
2019	112,049,000
2020-2024	603,352,000
Total	1,126,276,000
Post-retirement plans
Weighted average assumptions used for valuing benefit obligations
Discount rate (as a percent)	3.69%	4.36%
Weighted average assumptions used in calculating expense
Discount rate (as a percent)	4.36%	3.39%		3.31%	4.26%
Medical cost trend rates
Effect of 1% increase in the assumed health care cost trend rate on benefit obligation	100,000	500,000
Effect of 1% decrease in the assumed health care cost trend rate on benefit obligation	100,000	500,000
Expected benefit payments
2015	1,270,000
2016	1,188,000
2017	1,108,000
2018	1,031,000
2019	955,000
2020-2024	3,694,000
Total	$ 9,246,000