| **Consolidated Statements of Stockholders' Equity (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] | Parent [Member] | Noncontrolling interest [Member] |
|----------------------------------------------------------------------------------------------------|----------|-----------------------|-------------------------------------|----------------------------|--------------------------------------------------------|-------------------------|------------------------------------------------------------|-----------------|----------------------------------|
| Balance at Dec. 31, 2010                                                                           |     | $ 683                 | $ 2,200                             | $ 7,804                    | $ 326                                                  | $ (105)                 | $ (26)                                                     |            | $ 563                            |
| **Increase (Decrease) in Stockholders' Equity [Roll Forward]**                                     |     |                  |                                |                       |                                                   |                    |                                                       |            |                             |
| Net income (loss)                                                                                  | 628      |                  |                                | 612                        |                                                   |                    |                                                       |            | 16                               |
| Other comprehensive income (loss)                                                                  | 151      |                  |                                |                       | 143                                                    |                    |                                                       |            | 8                                |
| Dividends paid to common stockholders                                                              |     |                  |                                | (108)                      |                                                   |                    |                                                       |            |                             |
| Stock-based compensation                                                                           |     |                  | 4                                   |                       |                                                   | 3                       |                                                       |            |                             |
| (Increase) Decrease in notes receivable from the issuance of common stock                          |     |                  |                                |                       |                                                   |                    | 4                                                          |            |                             |
| Other                                                                                              |     |                  | 2                                   |                       |                                                   |                    |                                                       |            | (11)                             |
| Acquisition of CNA Surety noncontrolling interest                                                  |     |                  | (65)                                |                       | 19                                                     |                    |                                                       |            | (429)                            |
| Disposition of FICOH ownership interest                                                            |     |                  |                                |                       | (8)                                                    |                    |                                                       |            | (147)                            |
| Balance at Dec. 31, 2011                                                                           | 11,488   | 683                   | 2,141                               | 8,308                      | 480                                                    | (102)                   | (22)                                                       | 11,488          |                        |
| **Increase (Decrease) in Stockholders' Equity [Roll Forward]**                                     |     |                  |                                |                       |                                                   |                    |                                                       |            |                             |
| Net income (loss)                                                                                  | 628      |                  |                                | 628                        |                                                   |                    |                                                       |            |                        |
| Other comprehensive income (loss)                                                                  | 351      |                  |                                |                       | 351                                                    |                    |                                                       |            |                        |
| Dividends paid to common stockholders                                                              |     |                  |                                | (162)                      |                                                   |                    |                                                       |            |                             |
| Stock-based compensation                                                                           |     |                  | 5                                   |                       |                                                   | 3                       |                                                       |            |                             |
| (Increase) Decrease in notes receivable from the issuance of common stock                          |     |                  |                                |                       |                                                   |                    | 1                                                          |            |                             |
| Other                                                                                              |     |                  |                           |                       |                                                   |                    |                                                       |            |                        |
| Acquisition of CNA Surety noncontrolling interest                                                  |     |                  |                                |                       |                                                   |                    |                                                       |            |                        |
| Disposition of FICOH ownership interest                                                            |     |                  |                                |                       |                                                   |                    |                                                       |            |                        |
| Balance at Dec. 31, 2012                                                                           | 12,314   | 683                   | 2,146                               | 8,774                      | 831                                                    | (99)                    | (21)                                                       | 12,314          |                        |
| **Increase (Decrease) in Stockholders' Equity [Roll Forward]**                                     |     |                  |                                |                       |                                                   |                    |                                                       |            |                             |
| Net income (loss)                                                                                  | 937      |                  |                                | 937                        |                                                   |                    |                                                       |            |                        |
| Other comprehensive income (loss)                                                                  | (389)    |                  |                                |                       | (389)                                                  |                    |                                                       |            |                        |
| Dividends paid to common stockholders                                                              |     |                  |                                | (216)                      |                                                   |                    |                                                       |            |                             |
| Stock-based compensation                                                                           |     |                  | (1)                                 |                       |                                                   | 8                       |                                                       |            |                             |
| (Increase) Decrease in notes receivable from the issuance of common stock                          |     |                  |                                |                       |                                                   |                    | (2)                                                        |            |                             |
| Other                                                                                              |     |                  |                           |                       |                                                   |                    |                                                       |            |                        |
| Acquisition of CNA Surety noncontrolling interest                                                  |     |                  |                           |                       |                                              |                    |                                                       |            |                        |
| Disposition of FICOH ownership interest                                                            |     |                  |                                |                       |                                              |                    |                                                       |            |                        |
| Balance at Dec. 31, 2013                                                                           | $ 12,651 | $ 683                 | $ 2,145                             | $ 9,495                    | $ 442                                                  | $ (91)                  | $ (23)                                                     | $ 12,651        |                        |

| X                                                                                                                                                                                                                                                                                                                       |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Change in Equity related to changes in Notes Receivable from the Issuance of Common Stock
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                              |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Stock-based compensation includes compensation expense as well as vesting and exercising of shares
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.
+ References
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| X                                                                                                                                                                                   |
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of the reduction or elimination during the period of a noncontrolling interest resulting from the parent's loss of control and deconsolidation of the entity in which one or more outside parties had a noncontrolling interest.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after tax and reclassification adjustments of other comprehensive income (loss).
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This element represents movements included in the statement of changes in stockholders' equity which are not separately disclosed or provided for elsewhere in the taxonomy.
+ References
No definition available.
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