Restructuring Charges (Schedule of Changes in Restructuring Reserves) (Details) - USD ($)
$ in Millions |
3 Months Ended |
Mar. 31, 2018 |
Mar. 31, 2017 |
| Restructuring Cost and Reserve [Line Items] |
|
|
|
| Balance at beginning of period |
|
$ 15
|
$ 18
|
| Restructuring charges |
|
16
|
11
|
| Payments |
|
(12)
|
(13)
|
| Adjustments for non-cash charges |
[1] |
|
(3)
|
| Balance at end of period |
|
19
|
13
|
| Total restructuring charges incurred to date |
|
$ 154
|
|
| Expected completion date of restructuring activities |
|
Dec. 31, 2018
|
|
| Employee costs |
|
|
|
| Restructuring Cost and Reserve [Line Items] |
|
|
|
| Balance at beginning of period |
|
$ 8
|
10
|
| Restructuring charges |
|
5
|
1
|
| Payments |
|
(3)
|
(4)
|
| Adjustments for non-cash charges |
[1] |
|
0
|
| Balance at end of period |
|
10
|
7
|
| Total restructuring charges incurred to date |
|
67
|
|
| Facilities costs |
|
|
|
| Restructuring Cost and Reserve [Line Items] |
|
|
|
| Balance at beginning of period |
|
0
|
4
|
| Restructuring charges |
|
1
|
1
|
| Payments |
|
(1)
|
(5)
|
| Adjustments for non-cash charges |
[1] |
|
0
|
| Balance at end of period |
|
0
|
0
|
| Total restructuring charges incurred to date |
|
18
|
|
| Technology costs |
|
|
|
| Restructuring Cost and Reserve [Line Items] |
|
|
|
| Balance at beginning of period |
|
6
|
0
|
| Restructuring charges |
|
10
|
6
|
| Payments |
|
(7)
|
0
|
| Adjustments for non-cash charges |
[1] |
|
(3)
|
| Balance at end of period |
|
9
|
3
|
| Total restructuring charges incurred to date |
|
36
|
|
| Other costs |
|
|
|
| Restructuring Cost and Reserve [Line Items] |
|
|
|
| Balance at beginning of period |
|
1
|
4
|
| Restructuring charges |
|
0
|
3
|
| Payments |
|
(1)
|
(4)
|
| Adjustments for non-cash charges |
[1] |
|
0
|
| Balance at end of period |
|
0
|
$ 3
|
| Total restructuring charges incurred to date |
|
33
|
|
| Minimum |
|
|
|
| Restructuring Cost and Reserve [Line Items] |
|
|
|
| Total expected restructuring charges |
[2] |
185
|
|
| Minimum | Employee costs |
|
|
|
| Restructuring Cost and Reserve [Line Items] |
|
|
|
| Total expected restructuring charges |
[2] |
70
|
|
| Minimum | Facilities costs |
|
|
|
| Restructuring Cost and Reserve [Line Items] |
|
|
|
| Total expected restructuring charges |
[2] |
20
|
|
| Minimum | Technology costs |
|
|
|
| Restructuring Cost and Reserve [Line Items] |
|
|
|
| Total expected restructuring charges |
[2] |
60
|
|
| Minimum | Other costs |
|
|
|
| Restructuring Cost and Reserve [Line Items] |
|
|
|
| Total expected restructuring charges |
[2] |
35
|
|
| Maximum |
|
|
|
| Restructuring Cost and Reserve [Line Items] |
|
|
|
| Total expected restructuring charges |
[2] |
195
|
|
| Maximum | Employee costs |
|
|
|
| Restructuring Cost and Reserve [Line Items] |
|
|
|
| Total expected restructuring charges |
[2] |
70
|
|
| Maximum | Facilities costs |
|
|
|
| Restructuring Cost and Reserve [Line Items] |
|
|
|
| Total expected restructuring charges |
[2] |
25
|
|
| Maximum | Technology costs |
|
|
|
| Restructuring Cost and Reserve [Line Items] |
|
|
|
| Total expected restructuring charges |
[2] |
65
|
|
| Maximum | Other costs |
|
|
|
| Restructuring Cost and Reserve [Line Items] |
|
|
|
| Total expected restructuring charges |
[2] |
$ 35
|
|
|
|