v3.2.0.727

Acquisitions (Detail) - USD ($) $ / shares in Units, $ in Millions | Jun. 17, 2014 | Jun. 30, 2015 | Apr. 01, 2015 | Dec. 31, 2014 | Oct. 31, 2014 | Jun. 30, 2014 | [4] | Apr. 28, 2014 | Dec. 31, 2013 | [4]
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Business Acquisition - To be acquired [Line Items] |  |  |  |  |  |  |  |  |  |
Share Price |  | $ 101.68 |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |
Unpaid losses and loss expenses |  | $ 38,230 |  |  | $ 38,315 |  |  |  |  |
Unearned premiums |  | 8,879 |  |  | 8,222 |  |  |  |  |
Insurance and reinsurance balances receivable |  | 5,757 |  |  | 5,426 |  |  |  |  |
Cash |  | $ 790 | [1],[2] |  | $ 655 | [1],[3] |  | $ 594 |  | $ 579
The Siam Commercial Samaggi Insurance PCL [Member] |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |
Business Combination, Step Acquisition, Equity Interest in Acquiree, Percentage | 32.17% |  |  |  |  |  |  |  | 60.86% |
Business Acquisition, Purchase Price Allocation, Goodwill Amount |  |  |  |  |  |  |  |  | $ 46 |
Business Acquisition, Purchase Price Allocation, Intangible Assets Other than Goodwill |  |  |  |  |  |  |  |  | $ 80 |
Business Combination Total Ownership Percentage | 93.03% |  |  |  |  |  |  |  |  |
Business Combination, Consideration Transferred | $ 176 |  |  |  |  |  |  |  |  |
Large Corporate P&C Business Of Itau Seguros [Member] |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |
Business Acquisition, Purchase Price Allocation, Goodwill Amount |  |  |  |  |  |  | $ 449 |  |  |
Business Acquisition, Purchase Price Allocation, Intangible Assets Other than Goodwill |  |  |  |  |  |  | 60 |  |  |
Business Acquisition, Cost of Acquired Entity, Expected Cash Consideration |  |  |  |  |  |  | $ 610 |  |  |
Fireman's Fund high net worth personal lines [Member] |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |
Business Acquisition, Purchase Price Allocation, Goodwill Amount |  |  |  | $ 208 |  |  |  |  |  |
Business Acquisition, Purchase Price Allocation, Intangible Assets Other than Goodwill |  |  |  | 266 |  |  |  |  |  |
Business Acquisition, Cost of Acquired Entity, Expected Cash Consideration |  |  |  | 365 |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities |  |  |  | 858 |  |  |  |  |  |
Unpaid losses and loss expenses |  |  |  | 402 |  |  |  |  |  |
Unearned premiums |  |  |  | 428 |  |  |  |  |  |
Insurance and reinsurance balances receivable |  |  |  | 128 |  |  |  |  |  |
Cash |  |  |  | 620 |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets |  |  |  | $ 749 |  |  |  |  |  |
The Chubb Corporation [Member] |  |  |  |  |  |  |  |  |  |
Business Acquisition - To be acquired [Line Items] |  |  |  |  |  |  |  |  |  |
Business Acquisition, Cost of Acquired Entity, Expected Cash Consideration Per Share |  | $ 62.93 |  |  |  |  |  |  |  |
Business Acquisition, Cost of Acquired Entity, Expected Stock Consideration Per Share |  | 0.6019 |  |  |  |  |  |  |  |
Business Acquisition Expected Outstanding Share Ownership To Be Held By Acquired Company Shareholders |  | 137,000,000 |  |  |  |  |  |  |  |
Business Acquisition, Expected Outstanding Share Ownership To Be Held By Acquired Company Shareholders |  | 30.00% |  |  |  |  |  |  |  |
Business Acquisition, Cost of Acquired Entity, Expected Cash and Stock Consideration |  | $ 28,300 |  |  |  |  |  |  |  |
Business Acquisition, Expected Financing of Acquisition with Issuance of Senior Notes |  | 5,300 |  |  |  |  |  |  |  |
Business Acquisition, Expected Financing Of Acquisition With Cash |  | $ 9,000 |  |  |  |  |  |  |  |
[1] | ACE maintains two notional multicurrency cash pools (Pools) with a third-party bank. Various ACE entities participate in one or the other of the Pools, pursuant to which credit and debit balances in individual ACE accounts are translated daily into a single currency and pooled on a notional basis. Individual ACE entities are permitted to overdraw on their individual accounts provided the overall Pool balances do not fall below zero. At June 30, 2015 and December 31, 2014, the cash balance of one or more entities was negative; however, the overall Pool balances were positive.
[2] | ACE maintains two notional multicurrency cash pools (Pools) with a third-party bank. Various ACE entities participate in one or the other of the Pools, pursuant to which credit and debit balances in individual ACE accounts are translated daily into a single currency and pooled on a notional basis. Individual ACE entities are permitted to overdraw on their individual accounts provided the overall Pool balances do not fall below zero. At June 30, 2015, the cash balance of one or more entities was negative; however, the overall Pool balances were positive.
[3] | ACE maintains two notional multicurrency cash pools (Pools) with a third-party bank. Various ACE entities participate in one or the other of the Pools, pursuant to which credit and debit balances in individual ACE accounts are translated daily into a single currency and pooled on a notional basis. Individual ACE entities are permitted to overdraw on their individual accounts provided the overall Pool balances do not fall below zero. At December 31, 2014, the cash balance of one or more entities was negative; however, the overall Pool balances were positive.
[4] | ACE maintains two notional multicurrency cash pools (Pools) with a third-party bank. Various ACE entities participate in one or the other of the Pools, pursuant to which credit and debit balances in individual ACE accounts are translated daily into a single currency and pooled on a notional basis. Individual ACE entities are permitted to overdraw on their individual accounts provided the overall Pool balances do not fall below zero. At June 30, 2014 and December 31, 2013, the cash balance of one or more entities was negative; however, the overall Pool balances were positive.

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