| **Condensed Consolidated Statements of Stockholders' Equity (Unaudited) (USD $)In Millions, unless otherwise specified** | Total    | Common stock [Member] | Additional paid-in capital [Member] | Retained earnings [Member] | Accumulated other comprehensive income (loss) [Member] | Treasury stock [Member] | Notes receivable for the issuance of common stock [Member] |
|--------------------------------------------------------------------------------------------------------------------------|----------|-----------------------|-------------------------------------|----------------------------|--------------------------------------------------------|-------------------------|------------------------------------------------------------|
| Balance at Dec. 31, 2012                                                                                                 |     | $ 683                 | $ 2,146                             | $ 8,774                    | $ 831                                                  | $ (99)                  | $ (21)                                                     |
| **Increase (Decrease) in Stockholders' Equity [Roll Forward]**                                                           |     |                  |                                |                       |                                                   |                    |                                                       |
| Net income (loss)                                                                                                        | 250      |                  |                                | 250                        |                                                   |                    |                                                       |
| Other comprehensive income (loss), net of tax                                                                            | (104)    |                  |                                |                       | (104)                                                  |                    |                                                       |
| Dividends paid to common stockholders                                                                                    |     |                  |                                | (55)                       |                                                   |                    |                                                       |
| Stock-based compensation                                                                                                 |     |                  | (8)                                 |                       |                                                   | 7                       |                                                       |
| (Increase) Decrease in notes receivable from the issuance of common stock                                                |     |                  |                                |                       |                                                   |                    | 1                                                          |
| Balance at Mar. 31, 2013                                                                                                 | 12,405   | 683                   | 2,138                               | 8,969                      | 727                                                    | (92)                    | (20)                                                       |
| Balance at Dec. 31, 2013                                                                                                 | 12,651   | 683                   | 2,145                               | 9,495                      | 442                                                    | (91)                    | (23)                                                       |
| **Increase (Decrease) in Stockholders' Equity [Roll Forward]**                                                           |     |                  |                                |                       |                                                   |                    |                                                       |
| Net income (loss)                                                                                                        | 13       |                  |                                | 13                         |                                                   |                    |                                                       |
| Other comprehensive income (loss), net of tax                                                                            | 250      |                  |                                |                       | 250                                                    |                    |                                                       |
| Dividends paid to common stockholders                                                                                    |     |                  |                                | (338)                      |                                                   |                    |                                                       |
| Stock-based compensation                                                                                                 |     |                  | (1)                                 |                       |                                                   | 6                       |                                                       |
| (Increase) Decrease in notes receivable from the issuance of common stock                                                |     |                  |                                |                       |                                                   |                    | 1                                                          |
| Balance at Mar. 31, 2014                                                                                                 | $ 12,582 | $ 683                 | $ 2,144                             | $ 9,170                    | $ 692                                                  | $ (85)                  | $ (22)                                                     |

| X                                                                                                                                                                                                                                                                                                                       |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Change in Equity related to changes in Notes Receivable from the Issuance of Common Stock
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Stock-based compensation includes compensation expense as well as vesting and exercising of shares
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.
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| - Definition
Amount after tax and reclassification adjustments of other comprehensive income (loss).
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.
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