Retirement Benefits - Components of Periodic Benefit Cost for Corporation's Defined Benefit Pension and Postretirement Benefits Plans (Detail) - USD ($) $ in Thousands |
3 Months Ended | |
|---|---|---|
May 27, 2016 |
May 29, 2015 |
|
| Defined Benefit Pension Plans [Member] | ||
| Defined Benefit Plan Disclosure [Line Items] | ||
| Service cost | $ 186 | $ 159 |
| Interest cost | 1,593 | 1,558 |
| Expected return on plan assets | (1,528) | (1,668) |
| Amortization of prior service cost (credit) | 1 | 1 |
| Amortization of actuarial loss (gain) | 873 | 848 |
| Defined benefit plan, net periodic benefit cost, total | 1,125 | 898 |
| Postretirement Benefits Plans [Member] | ||
| Defined Benefit Plan Disclosure [Line Items] | ||
| Service cost | 86 | 125 |
| Interest cost | 528 | 525 |
| Expected return on plan assets | (582) | (675) |
| Amortization of prior service cost (credit) | (175) | (175) |
| Amortization of actuarial loss (gain) | (367) | (300) |
| Defined benefit plan, net periodic benefit cost, total | $ (510) | $ (500) |