|
Retirement Benefit Plans (Level 3 Investment Assets) (Details) (USD $)
In Millions, unless otherwise specified
|
12 Months Ended |
|
Jan. 28, 2012
|
Jan. 29, 2011
|
|
Corporate bonds [Member]
|
|
|
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
|
|
| Balance, beginning of year |
$ 4 |
|
| Transfers, net |
11 |
|
| Realized gains |
|
4 |
| Unrealized gains/(losses) |
(1) |
|
| Purchases and issuances |
33 |
|
| Sales, maturities and settlements |
(11) |
|
| Balance, end of year |
36 |
4 |
|
Private Equity Funds [Member]
|
|
|
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
|
|
| Balance, beginning of year |
291 |
252 |
| Realized gains |
33 |
21 |
| Unrealized gains/(losses) |
(17) |
19 |
| Purchases and issuances |
53 |
46 |
| Sales, maturities and settlements |
(61) |
(47) |
| Balance, end of year |
299 |
291 |
|
Real Estate [Member]
|
|
|
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
|
|
| Balance, beginning of year |
251 |
231 |
| Realized gains |
10 |
15 |
| Unrealized gains/(losses) |
24 |
(31) |
| Purchases and issuances |
12 |
61 |
| Sales, maturities and settlements |
(42) |
(25) |
| Balance, end of year |
$ 255 |
$ 251 |