| **Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Millions** | Total    | Common Stock | Additional Paid-in Capital | Retained Earnings | AOCI Attributable to Parent | Treasury Stock |
|---------------------------------------------------------------------------------------------------|----------|--------------|----------------------------|-------------------|-----------------------------|----------------|
| Balance, beginning of year at Dec. 31, 2015                                                       |     | $ 683        | $ 2,153                    | $ 9,313           | $ (315)                     | $ (78)         |
| Stock-based compensation                                                                          |     |         | 2                          |              |                        | 5              |
| Dividends paid to common stockholders                                                             |     |         |                       | (677)             |                        |           |
| Net income                                                                                        | $ 275    |         |                       | 275               |                        |           |
| Other comprehensive income                                                                        | 525      |         |                       |              | 525                         |           |
| Balance, end of period at Jun. 30, 2016                                                           | 11,886   | 683          | 2,155                      | 8,911             | 210                         | (73)           |
| Balance, beginning of year at Mar. 31, 2016                                                       |     |         |                       |              | (56)                        |           |
| Net income                                                                                        | 209      |         |                       |              |                        |           |
| Other comprehensive income                                                                        | 266      |         |                       |              |                        |           |
| Balance, end of period at Jun. 30, 2016                                                           | 11,886   | 683          | 2,155                      | 8,911             | 210                         | (73)           |
| Balance, beginning of year at Dec. 31, 2016                                                       | 11,969   | 683          | 2,173                      | 9,359             | (173)                       | (73)           |
| Stock-based compensation                                                                          |     |         | (6)                        |              |                        | 8              |
| Dividends paid to common stockholders                                                             |     |         |                       | (680)             |                        |           |
| Net income                                                                                        | 532      |         |                       | 532               |                        |           |
| Other comprehensive income                                                                        | 205      |         |                       |              | 205                         |           |
| Balance, end of period at Jun. 30, 2017                                                           | 12,028   | 683          | 2,167                      | 9,211             | 32                          | (65)           |
| Balance, beginning of year at Mar. 31, 2017                                                       |     |         |                       |              | (92)                        |           |
| Net income                                                                                        | 272      |         |                       |              |                        |           |
| Other comprehensive income                                                                        | 124      |         |                       |              |                        |           |
| Balance, end of period at Jun. 30, 2017                                                           | $ 12,028 | $ 683        | $ 2,167                    | $ 9,211           | $ 32                        | $ (65)         |

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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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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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