Information Provided In Connection With Outstanding Debt Of Subsidiaries (Condensed Consolidating Balance Sheet) (Detail) - USD ($) $ in Millions |
Jun. 30, 2015 |
Dec. 31, 2014 |
Jun. 30, 2014 |
Dec. 31, 2013 |
[4] | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Condensed Financial Statements, Captions [Line Items] | ||||||||||||||||
| Investments | $ 63,265 | $ 62,904 | ||||||||||||||
| Cash | 790 | [1],[2] | 655 | [1],[3] | $ 594 | [4] | $ 579 | |||||||||
| Insurance and reinsurance balances receivable | 5,757 | 5,426 | ||||||||||||||
| Reinsurance recoverable on losses and loss expenses | 11,775 | 11,992 | ||||||||||||||
| Reinsurance recoverable on policy benefits | 203 | 217 | ||||||||||||||
| Value of business acquired | 434 | 466 | ||||||||||||||
| Goodwill and other intangible assets | 5,969 | 5,724 | ||||||||||||||
| Investments in subsidiaries | 0 | 0 | ||||||||||||||
| Due from subsidiaries and affiliates, net | 0 | 0 | ||||||||||||||
| Other assets | 11,647 | 10,864 | ||||||||||||||
| Total assets | 99,840 | 98,248 | ||||||||||||||
| Unpaid losses and loss expenses | 38,230 | 38,315 | ||||||||||||||
| Unearned premiums | 8,879 | 8,222 | ||||||||||||||
| Future policy benefits | 4,835 | 4,754 | ||||||||||||||
| Due to subsidiaries and affiliates, net | 0 | 0 | ||||||||||||||
| Short-term debt | 2,102 | 2,552 | ||||||||||||||
| Affiliated notional cash pooling programs | 0 | 0 | ||||||||||||||
| Long-term debt | 4,157 | 3,357 | ||||||||||||||
| Trust preferred securities | 309 | 309 | ||||||||||||||
| Other liabilities | 11,773 | 11,152 | ||||||||||||||
| Total liabilities | 70,285 | 68,661 | ||||||||||||||
| Total shareholders' equity | 29,555 | 29,587 | 30,325 | |||||||||||||
| Total liabilities and shareholders’ equity | 99,840 | 98,248 | ||||||||||||||
| ACE Limited (Parent Guarantor) | ||||||||||||||||
| Condensed Financial Statements, Captions [Line Items] | ||||||||||||||||
| Investments | 32 | 30 | ||||||||||||||
| Cash | 1 | [1],[2] | 0 | [1],[3] | 44 | [4] | 0 | |||||||||
| Insurance and reinsurance balances receivable | 0 | 0 | ||||||||||||||
| Reinsurance recoverable on losses and loss expenses | 0 | 0 | ||||||||||||||
| Reinsurance recoverable on policy benefits | 0 | 0 | ||||||||||||||
| Value of business acquired | 0 | 0 | ||||||||||||||
| Goodwill and other intangible assets | 0 | 0 | ||||||||||||||
| Investments in subsidiaries | 29,806 | 29,497 | ||||||||||||||
| Due from subsidiaries and affiliates, net | 370 | 583 | ||||||||||||||
| Other assets | 5 | 4 | ||||||||||||||
| Total assets | 30,214 | 30,114 | ||||||||||||||
| Unpaid losses and loss expenses | 0 | 0 | ||||||||||||||
| Unearned premiums | 0 | |||||||||||||||
| Future policy benefits | 0 | 0 | ||||||||||||||
| Due to subsidiaries and affiliates, net | 0 | 0 | ||||||||||||||
| Short-term debt | 0 | 0 | ||||||||||||||
| Affiliated notional cash pooling programs | 386 | [2] | 246 | [3] | ||||||||||||
| Long-term debt | 0 | 0 | ||||||||||||||
| Trust preferred securities | 0 | 0 | ||||||||||||||
| Other liabilities | 273 | 281 | ||||||||||||||
| Total liabilities | 659 | 527 | ||||||||||||||
| Total shareholders' equity | 29,555 | 29,587 | ||||||||||||||
| Total liabilities and shareholders’ equity | 30,214 | 30,114 | ||||||||||||||
| ACE INA Holdings Inc (Subsidiary Issuer) | ||||||||||||||||
| Condensed Financial Statements, Captions [Line Items] | ||||||||||||||||
| Investments | 35 | 225 | ||||||||||||||
| Cash | 3 | [1],[2] | 1 | [1],[3] | 1 | [4] | 16 | |||||||||
| Insurance and reinsurance balances receivable | 0 | 0 | ||||||||||||||
| Reinsurance recoverable on losses and loss expenses | 0 | 0 | ||||||||||||||
| Reinsurance recoverable on policy benefits | 0 | 0 | ||||||||||||||
| Value of business acquired | 0 | 0 | ||||||||||||||
| Goodwill and other intangible assets | 0 | 0 | ||||||||||||||
| Investments in subsidiaries | 18,747 | 18,762 | ||||||||||||||
| Due from subsidiaries and affiliates, net | 0 | 0 | ||||||||||||||
| Other assets | 381 | 295 | ||||||||||||||
| Total assets | 19,166 | 19,283 | ||||||||||||||
| Unpaid losses and loss expenses | 0 | 0 | ||||||||||||||
| Unearned premiums | 0 | |||||||||||||||
| Future policy benefits | 0 | 0 | ||||||||||||||
| Due to subsidiaries and affiliates, net | 245 | 422 | ||||||||||||||
| Short-term debt | 700 | 1,150 | ||||||||||||||
| Affiliated notional cash pooling programs | 37 | [2] | 309 | [3] | ||||||||||||
| Long-term debt | 4,145 | 3,345 | ||||||||||||||
| Trust preferred securities | 309 | 309 | ||||||||||||||
| Other liabilities | 1,499 | 1,404 | ||||||||||||||
| Total liabilities | 6,935 | 6,939 | ||||||||||||||
| Total shareholders' equity | 12,231 | 12,344 | ||||||||||||||
| Total liabilities and shareholders’ equity | 19,166 | 19,283 | ||||||||||||||
| Other ACE Limited Subsidiaries | ||||||||||||||||
| Condensed Financial Statements, Captions [Line Items] | ||||||||||||||||
| Investments | 63,198 | 62,649 | ||||||||||||||
| Cash | 1,209 | [1],[2] | 1,209 | [1],[3] | 1,026 | [4] | 748 | |||||||||
| Insurance and reinsurance balances receivable | 6,726 | 6,178 | ||||||||||||||
| Reinsurance recoverable on losses and loss expenses | 20,619 | 20,992 | ||||||||||||||
| Reinsurance recoverable on policy benefits | 1,192 | 1,194 | ||||||||||||||
| Value of business acquired | 434 | 466 | ||||||||||||||
| Goodwill and other intangible assets | 5,969 | 5,724 | ||||||||||||||
| Investments in subsidiaries | 0 | 0 | ||||||||||||||
| Due from subsidiaries and affiliates, net | 0 | 0 | ||||||||||||||
| Other assets | 15,026 | 14,196 | ||||||||||||||
| Total assets | 114,373 | 112,608 | ||||||||||||||
| Unpaid losses and loss expenses | 46,596 | 46,770 | ||||||||||||||
| Unearned premiums | 10,718 | 9,958 | ||||||||||||||
| Future policy benefits | 5,824 | 5,731 | ||||||||||||||
| Due to subsidiaries and affiliates, net | 125 | 161 | ||||||||||||||
| Short-term debt | 1,402 | 1,402 | ||||||||||||||
| Affiliated notional cash pooling programs | 0 | [2] | 0 | [3] | ||||||||||||
| Long-term debt | 12 | 12 | ||||||||||||||
| Trust preferred securities | 0 | 0 | ||||||||||||||
| Other liabilities | 13,374 | 12,659 | ||||||||||||||
| Total liabilities | 78,051 | 76,693 | ||||||||||||||
| Total shareholders' equity | 36,322 | 35,915 | ||||||||||||||
| Total liabilities and shareholders’ equity | 114,373 | 112,608 | ||||||||||||||
| Consolidating Adjustments and Eliminations | ||||||||||||||||
| Condensed Financial Statements, Captions [Line Items] | ||||||||||||||||
| Investments | 0 | 0 | ||||||||||||||
| Cash | (423) | [1],[2] | (555) | [1],[3] | $ (477) | [4] | $ (185) | |||||||||
| Insurance and reinsurance balances receivable | (969) | (752) | ||||||||||||||
| Reinsurance recoverable on losses and loss expenses | (8,844) | (9,000) | ||||||||||||||
| Reinsurance recoverable on policy benefits | (989) | (977) | ||||||||||||||
| Value of business acquired | 0 | 0 | ||||||||||||||
| Goodwill and other intangible assets | 0 | 0 | ||||||||||||||
| Investments in subsidiaries | (48,553) | (48,259) | ||||||||||||||
| Due from subsidiaries and affiliates, net | (370) | (583) | ||||||||||||||
| Other assets | (3,765) | (3,631) | ||||||||||||||
| Total assets | (63,913) | (63,757) | ||||||||||||||
| Unpaid losses and loss expenses | (8,366) | (8,455) | ||||||||||||||
| Unearned premiums | (1,839) | (1,736) | ||||||||||||||
| Future policy benefits | (989) | (977) | ||||||||||||||
| Due to subsidiaries and affiliates, net | (370) | (583) | ||||||||||||||
| Short-term debt | 0 | 0 | ||||||||||||||
| Affiliated notional cash pooling programs | (423) | [2] | (555) | [3] | ||||||||||||
| Long-term debt | 0 | 0 | ||||||||||||||
| Trust preferred securities | 0 | 0 | ||||||||||||||
| Other liabilities | (3,373) | (3,192) | ||||||||||||||
| Total liabilities | (15,360) | (15,498) | ||||||||||||||
| Total shareholders' equity | (48,553) | (48,259) | ||||||||||||||
| Total liabilities and shareholders’ equity | $ (63,913) | $ (63,757) | ||||||||||||||
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