The value of the shares of ACE Capital Trust II purchased by ACE INA.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Debt (Narrative) (Details) - USD ($) $ in Millions		12 Months Ended
Debt (Narrative) (Details) - USD ($) $ in Millions	Jan. 14, 2016	Dec. 31, 2016	Dec. 31, 2015	Mar. 31, 2000
Debt Instrument [Line Items]
Short-term debt		$ 500.0	$ 0.0
Debt issued		1,000.0
Current amount of long-term debt outstanding		12,610.0	9,389.0
Chubb INA Capital Securities Due 2067 [Member]
Debt Instrument [Line Items]
Debt issued		$ 1,000.0
Junior Subordinated Debt [Member] \| Chubb INA Capital Securities Due 2067 [Member]
Debt Instrument [Line Items]
Long-term debt stated interest rate		6.375%
Debt issued		$ 962.0	0.0
Junior Subordinated Debt [Member] \| Chubb INA Capital Securities Due 2067 [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		2.25%
Senior Notes [Member]
Debt Instrument [Line Items]
Current amount of long-term debt outstanding		$ 12,610.0	9,389.0
Senior Notes [Member] \| INA Senior Notes Due February 2017 [Member]
Debt Instrument [Line Items]
Short-term debt		$ 500.0	0.0
Long-term debt stated interest rate		5.70%
Debt issued		$ 500.0
Current amount of long-term debt outstanding		$ 0.0	$ 500.0
Trust Preferred Securities \| INA capital securities due 2030
Debt Instrument [Line Items]
Long-term debt stated interest rate		9.70%		9.70%
Debt issued		$ 309.0		$ 300.0
ACE Capital Trust II common securities purchased				$ 9.2
The Chubb Corporation [Member]
Debt Instrument [Line Items]
Business Combination, Consideration Transferred, Liabilities Incurred	$ 5,300.0
Debt issued	3,300.0
Current amount of long-term debt outstanding	$ 3,765.0