Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified	Jun. 30, 2014		Dec. 31, 2013
Investments [Abstract]
Fixed maturities available for sale, at fair value (amortized cost - $49,719 and $48,406) (includes hybrid financial instruments of $305 and $302)	$ 51,601		$ 49,254
Fixed maturities held to maturity, at amortized cost (fair value – $6,015 and $6,263)	5,774		6,098
Equity securities, at fair value (cost – $874 and $841)	907		837
Short-term investments, at fair value and amortized cost	2,108		1,763
Other investments (cost – $2,876 and $2,671)	3,230		2,976
Total investments	63,620		60,928
Cash	594	[1],[2]	579	[1],[3]
Securities lending collateral	1,440		1,632
Accrued investment income	556		556
Insurance and reinsurance balances receivable	5,316		5,026
Reinsurance recoverable on losses and loss expenses	10,768		11,227
Reinsurance recoverable on policy benefits	234		218
Deferred policy acquisition costs	2,562		2,313
Value of business acquired	514		536
Goodwill and other intangible assets	5,522		5,404
Prepaid reinsurance premiums	1,867		1,675
Deferred tax assets	234		616
Investments in partially-owned insurance companies	470		470
Other assets	3,750		3,330
Total assets	97,447		94,510
Liabilities
Unpaid losses and loss expenses	37,177		37,443
Unearned premiums	8,296		7,539
Future policy benefits	4,778		4,615
Insurance and reinsurance balances payable	3,794		3,628
Securities lending payable	1,441		1,633
Accounts payable, accrued expenses, and other liabilities	5,419		4,810
Short-term debt	1,851		1,901
Long-term debt	4,057		3,807
Trust preferred securities	309		309
Total liabilities	67,122		65,685
Commitments and contingencies
Shareholders’ equity
Common Shares (CHF 26.01 and CHF 27.04 par value; 342,832,412 shares issued; 336,225,589 and 339,793,935 shares outstanding)	8,501		8,899
Common Shares in treasury (6,606,823 and 3,038,477 shares)	(630)		(255)
Additional paid-in capital	5,055		5,238
Retained earnings	15,304		13,791
Accumulated other comprehensive income (AOCI)	2,095		1,152
Total shareholders’ equity	30,325		28,825
Total liabilities and shareholders’ equity	$ 97,447		$ 94,510

[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, 2014 and December 31, 2013, 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, 2014, 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, 2013, the cash balance of one or more entities was negative; however, the overall Pool balances were positive.