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BENEFIT PLANS - Narrative (Details) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Apr. 27, 2019 USD ($) employee agreement | Apr. 28, 2018 USD ($) | Apr. 27, 2019 USD ($) employee agreement | Apr. 28, 2018 USD ($) | Aug. 01, 2020 agreement employee | Aug. 03, 2019 agreement employee | Oct. 22, 2018
Pension Plans, Postretirement and Other Employee Benefits [Line Items] |  |  |  |  |  |  |
Multiemployer Plans, Withdrawal Obligation | $ 35.7 |  | $ 35.7 |  |  |  |
Impact to service and interest cost with a 100 basis point increase in the trend rate |  |  | 0.0 |  |  |  |
Company's accumulated postretirement benefit obligation would impact due to a 100 basis point decrease in the trend rate |  |  | 2.7 |  |  |  |
Company's accumulated postretirement benefit obligation would impact due to a 100 basis point increase in the trend rate |  |  | 3.2 |  |  |  |
Employer contribution in defined contribution plans |  |  | $ 20.8 | $ 8.6 |  |  |
Company's number of employees (employees) | employee | 19,000 |  | 19,000 |  |  |  |
Number of employees covered by collective bargaining agreements (employees) | employee | 5,000 |  | 5,000 |  |  |  |
Number of collective bargaining agreements for covered employees (agreements) | agreement | 47 |  | 47 |  |  |  |
Number of initial collective bargaining agreements (agreements) | agreement | 2 |  | 2 |  |  |  |
Number of employees covered by initial collective bargaining agreements (employees) | employee | 24 |  | 24 |  |  |  |
Number of collective bargaining agreements covering employees renegotiated (agreements) | agreement |  |  | 9 |  |  |  |
Number of employees renegotiated collective bargaining agreement (employees) | employee |  |  | 800 |  |  |  |
Number of collective bargaining agreements covering employees expired without renegotiated (agreements) | agreement |  |  | 400 |  |  |  |
Maximum |  |  |  |  |  |  |
Pension Plans, Postretirement and Other Employee Benefits [Line Items] |  |  |  |  |  |  |
Expected employer contributions in current fiscal year | $ 10.0 |  | $ 10.0 |  |  |  |
Minimum |  |  |  |  |  |  |
Pension Plans, Postretirement and Other Employee Benefits [Line Items] |  |  |  |  |  |  |
Expected employer contributions in current fiscal year | 5.0 |  | 5.0 |  |  |  |
Multiemployer Postretirement Benefit |  |  |  |  |  |  |
Pension Plans, Postretirement and Other Employee Benefits [Line Items] |  |  |  |  |  |  |
Contribution to multi-employer plans | $ 13.8 | $ 0.1 | 27.4 | $ 0.4 |  |  |
Post-Employment Benefits | Retirement Plan, Before Age 65 [Member] |  |  |  |  |  |  |
Pension Plans, Postretirement and Other Employee Benefits [Line Items] |  |  |  |  |  |  |
Assumed healthcare cost trend rate |  |  |  |  |  |  | 7.80%
Assumed healthcare cost ultimate trend rate |  |  |  |  |  |  | 4.50%
Post-Employment Benefits | Retirement Plan, After Age 65 [Member] |  |  |  |  |  |  |
Pension Plans, Postretirement and Other Employee Benefits [Line Items] |  |  |  |  |  |  |
Assumed healthcare cost trend rate |  |  |  |  |  |  | 8.70%
Assumed healthcare cost ultimate trend rate |  |  |  |  |  |  | 4.50%
Scenario, Forecast [Member] |  |  |  |  |  |  |
Pension Plans, Postretirement and Other Employee Benefits [Line Items] |  |  |  |  |  |  |
Number of collective bargaining agreements covering employees expired (agreements) | agreement |  |  |  |  | 6 | 6 |
Number of employee expire collective bargaining agreement (employees) | employee |  |  |  |  | 500 | 670 |
Health and Welfare Plan | Multiemployer Postretirement Benefit |  |  |  |  |  |  |
Pension Plans, Postretirement and Other Employee Benefits [Line Items] |  |  |  |  |  |  |
Contribution to multi-employer plans |  |  | $ 42.3 |  |  |  |

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