Schedule II (STATEMENTS OF CASH FLOWS - Parent Company Only) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013
Condensed Financial Statements, Captions [Line Items]
Net cash flows from operating activities		$ 3,864		$ 4,496		$ 4,022
Purchases of fixed maturities available for sale		(16,040)		(15,553)		(21,340)
Sales of fixed maturities available for sale		10,783		7,482		10,355
Net change in short-term investments		(8,216)		(603)		524
Net derivative instruments settlements		(21)		(230)		(471)
Other		263		274		393
Net cash flows used for investing activities		(6,294)		(2,504)		(4,442)
Dividends paid on Common Shares		(862)		(862)		(517)
Proceeds from issuance of repurchase agreements		2,029		1,978		2,572
Repayments of Short-term Debt		2,027		1,977		2,572
Net proceeds from (payments to) affiliated notional cash pooling programs	[1]					0
Proceeds from share-based compensation plans		131		127		135
Net cash flows (used for) from financing activities		3,695		(1,777)		391
Net increase (decrease) in cash		1,120		76		(36)
Cash – beginning of year		655	[2],[3],[4]	579	[1],[2]	615	[1]
Cash – end of year		1,775	[3],[5]	655	[2],[3],[4]	579	[1],[2]
Parent Company Only
Condensed Financial Statements, Captions [Line Items]
Net cash flows from operating activities		3,125		541		970
Net change in short-term investments		0		0		(1)
Net derivative instruments settlements		0		0		0
Capital contributions to subsidiaries		(2,670)		0		(133)
Other						0
Net cash flows used for investing activities		(2,670)		0		(134)
Dividends paid on Common Shares		(862)		(862)		(517)
Repayments of Short-term Debt						0
Advances (to) from affiliates		(228)		260		(621)
Net proceeds from (payments to) affiliated notional cash pooling programs		636	[3]	61		185	[1]
Proceeds from share-based compensation plans		0		0		14
Net cash flows (used for) from financing activities		(454)		(541)		(939)
Net increase (decrease) in cash		1		0		(103)
Cash – beginning of year		0		0	[1]	103	[1]
Cash – end of year		$ 1	[3],[5]	$ 0		$ 0	[1]

[1] Chubb maintains two notional multi-currency cash pools (Pools) with a third-party bank. Refer to Note 1 f) for additional information. At December 31, 2013 and 2012, the cash balance of one or more entities was negative; however, the overall Pool balances were positive.

[2] Chubb maintains two notional multi-currency cash pools (Pools) with a third-party bank. Refer to Note 1 f) for additional information. At December 31, 2014 and 2013, the cash balance of one or more entities was negative; however, the overall Pool balances were positive.

[3] Chubb maintains two notional multi-currency cash pools (Pools) with a third-party bank. Refer to Note 1 f) for additional information. At December 31, 2015 and 2014, the cash balance of one or more entities was negative; however, the overall Pool balances were positive.

[4] Chubb maintains two notional multicurrency cash pools (Pools) with a third-party bank. Refer to Note 1 f) for additional information. At December 31, 2014, the cash balance of one or more entities was negative; however, the overall Pool balances were positive.

[5] Chubb maintains two notional multicurrency cash pools (Pools) with a third-party bank. Refer to Note 1 f) for additional information. At December 31, 2015, the cash balance of one or more entities was negative; however, the overall Pool balances were positive.