Schedule II (BALANCE SHEETS - Parent Company Only) (Details) - USD ($) $ in Millions		Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013	[5]	Dec. 31, 2012	[5]
Assets
Short-term investments		$ 10,446		$ 2,322
Other investments		3,291		3,346
Cash		1,775	[1],[2]	655	[1],[3],[4]	$ 579	[3]	$ 615
Other assets		3,881		3,556
Total assets		102,366		98,248
Liabilities
Accounts payable, accrued expenses, and other liabilities		6,205		5,726
Bank Overdrafts	[4]			0
Short-term debt				1,150
Total liabilities		73,231		68,661
Stockholders' Equity Attributable to Parent [Abstract]
Common Shares		7,833		8,055
Common Shares in treasury		(1,922)		(1,448)
Additional paid-in capital		4,481		5,145
Retained earnings		19,478		16,644
Accumulated other comprehensive income		(735)		1,191
Total liabilities and shareholders’ equity		102,366		98,248
Parent Company Only
Assets
Investments in subsidiaries and affiliates on equity basis		29,612		29,497
Short-term investments		1		1
Other investments		27		29
Total investments		29,640		29,527
Cash		1	[1],[2]	0		$ 0		$ 103
Due from subsidiaries and affiliates, net		644		583
Other assets		8		4
Total assets		30,293		30,114
Liabilities
Accounts payable, accrued expenses, and other liabilities		276		281
Bank Overdrafts		882	[2]	246	[4]
Total liabilities		1,158		527
Stockholders' Equity Attributable to Parent [Abstract]
Common Shares		7,833		8,055
Common Shares in treasury		(1,922)		(1,448)
Additional paid-in capital		4,481		5,145
Retained earnings		19,478		16,644
Accumulated other comprehensive income		(735)		1,191
Total shareholders' equity		29,135		29,587
Total liabilities and shareholders’ equity		$ 30,293		$ 30,114

[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, 2015 and 2014, the cash balance of one or more entities was negative; however, the overall Pool balances were positive.

[2] 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.

[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, 2014 and 2013, 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 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.