|
Retirement Benefit Plans (Level 3 Investment Assets) (Details) (USD $)
In Millions, unless otherwise specified
|
12 Months Ended |
|
Jan. 31, 2015
|
Feb. 01, 2014
|
| Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
|
|
| Number of hedge fund managers (more than) |
30 |
|
| Corporate bonds [Member] |
|
|
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
|
|
| Balance, beginning of year |
$ 11 |
$ 10 |
| Transfers, net |
0 |
|
| Realized gains |
0 |
0 |
| Unrealized gains/(losses) |
(1) |
(1) |
| Purchases and issuances |
5 |
2 |
| Sales, maturities and settlements |
(8) |
0 |
| Balance, end of year |
7 |
11 |
| Corporate loans [Member] |
|
|
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
|
|
| Balance, beginning of year |
6 |
12 |
| Transfers, net |
0 |
|
| Realized gains |
0 |
0 |
| Unrealized gains/(losses) |
0 |
0 |
| Purchases and issuances |
4 |
2 |
| Sales, maturities and settlements |
(5) |
(8) |
| Balance, end of year |
5 |
6 |
| Hedge Funds [Member] |
|
|
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
|
|
| Balance, beginning of year |
153 |
0 |
| Transfers, net |
0 |
|
| Realized gains |
13 |
0 |
| Unrealized gains/(losses) |
(4) |
3 |
| Purchases and issuances |
467 |
150 |
| Sales, maturities and settlements |
(315) |
0 |
| Balance, end of year |
314 |
153 |
| Private Equity Funds [Member] |
|
|
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
|
|
| Balance, beginning of year |
298 |
297 |
| Transfers, net |
0 |
|
| Realized gains |
57 |
38 |
| Unrealized gains/(losses) |
(8) |
3 |
| Purchases and issuances |
31 |
33 |
| Sales, maturities and settlements |
(97) |
(73) |
| Balance, end of year |
281 |
298 |
| Private real estate [Member] |
|
|
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
|
|
| Balance, beginning of year |
204 |
231 |
| Transfers, net |
0 |
|
| Realized gains |
3 |
5 |
| Unrealized gains/(losses) |
17 |
11 |
| Purchases and issuances |
3 |
4 |
| Sales, maturities and settlements |
(74) |
(47) |
| Balance, end of year |
$ 153 |
$ 204 |