Schedule II (BALANCE SHEETS - Parent Company Only) (Details) - USD ($) $ in Millions	Dec. 31, 2016		Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013	[5]
Assets
Short-term investments	$ 3,002		$ 10,446
Other investments	4,519		3,291
Cash	985	[1],[2]	1,775	[1],[3],[4]	$ 655	[1],[5]	$ 579
Other assets	5,090		3,821
Total assets	159,786		102,306
Liabilities
Accounts payable, accrued expenses, and other liabilities	8,617		6,205
Affiliated notional cash pooling program	300		0	[4]
Short-term debt	500		0
Total liabilities	111,511		73,171
Stockholders' Equity Attributable to Parent [Abstract]
Common Shares	11,121		7,833
Common Shares in treasury	(1,480)		(1,922)
Additional paid-in capital	15,335		4,481
Retained earnings	23,613		19,478
Accumulated other comprehensive income	(314)		(735)
Total shareholders' equity	48,275		29,135		29,587
Total liabilities and shareholders’ equity	159,786		102,306
Parent Company Only
Assets
Investments in subsidiaries and affiliates on equity basis	38,408		29,612
Short-term investments	2		1
Other investments	25		27
Total investments	38,435		29,640
Cash	1	[1],[2]	1	[1],[3],[4]	$ 0	[5]	$ 0
Due from subsidiaries and affiliates, net	10,482		644
Other assets	3		8
Total assets	48,921		30,293
Liabilities
Accounts payable, accrued expenses, and other liabilities	283		276
Affiliated notional cash pooling program	363	[2]	882	[4]
Total liabilities	646		1,158
Stockholders' Equity Attributable to Parent [Abstract]
Common Shares	11,121		7,833
Common Shares in treasury	(1,480)		(1,922)
Additional paid-in capital	15,335		4,481
Retained earnings	23,613		19,478
Accumulated other comprehensive income	(314)		(735)
Total shareholders' equity	48,275		29,135
Total liabilities and shareholders’ equity	$ 48,921		$ 30,293

[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, 2016 and 2015, 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, 2016, 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, 2015, 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, 2014 and 2013, the cash balance of one or more entities was negative; however, the overall Pool balances were positive.