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

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Upon election of early redemption, the interest rate percentage in addition to the applicable Treasury Rate which is required to be paid by the Company.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Debt (Narrative) (Details) € in Millions, $ in Millions	12 Months Ended
Debt (Narrative) (Details) € in Millions, $ in Millions	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Mar. 31, 2018 EUR (€)	Mar. 31, 2000 USD ($)
Junior Subordinated Debt [Member] \| Chubb INA Capital Securities Due 2067 [Member]
Debt Instrument [Line Items]
Long-term debt stated interest rate			6.375%
Debt Instrument, Face Amount			$ 1,000.0
Senior Notes [Member] \| INA Senior Notes Due March 2018 [Member]
Debt Instrument [Line Items]
Long-term debt stated interest rate				5.80%	5.80%
Debt Instrument, Face Amount				$ 300.0
Senior Notes [Member] \| INA Senior Notes Due May 2018 [Member]
Debt Instrument [Line Items]
Long-term debt stated interest rate			5.75%
Debt Instrument, Face Amount			$ 600.0
Senior Notes [Member] \| INA Senior Note Due August 2018 [Member]
Debt Instrument [Line Items]
Long-term debt stated interest rate		6.60%
Debt Instrument, Face Amount		$ 100.0
Senior Notes [Member] \| INA Senior Note Due March 2028 [Member]
Debt Instrument [Line Items]
Long-term debt stated interest rate				1.55%	1.55%
Make Whole Premium Additional Percent				0.15%	0.15%
Debt Instrument, Face Amount				$ 1,100.0	€ 900
Senior Notes [Member] \| INA Senior Note Due March 2038 [Member]
Debt Instrument [Line Items]
Long-term debt stated interest rate				2.50%	2.50%
Make Whole Premium Additional Percent				0.25%	0.25%
Debt Instrument, Face Amount				$ 1,100.0	€ 900
Trust Preferred Securities \| INA capital securities due 2030
Debt Instrument [Line Items]
Long-term debt stated interest rate	9.70%					9.70%
ACE Capital Trust II common securities purchased						$ 9.2
Debt Instrument, Face Amount	$ 309.0					$ 300.0
Junior Subordinated Debt [Member] \| Chubb INA Capital Securities Due 2067 [Member]
Debt Instrument [Line Items]
Gain (Loss) on Extinguishment of Debt	$ (36.0)
Senior Notes [Member] \| INA Senior Notes Due March 2018 [Member]
Debt Instrument [Line Items]
Long-term debt stated interest rate	5.80%
Make Whole Premium Additional Percent	0.35%
Debt Instrument, Face Amount	$ 300.0
Senior Notes [Member] \| INA Senior Notes Due May 2018 [Member]
Debt Instrument [Line Items]
Long-term debt stated interest rate	5.75%
Make Whole Premium Additional Percent	0.30%
Debt Instrument, Face Amount	$ 600.0
Senior Notes [Member] \| INA Senior Note Due August 2018 [Member]
Debt Instrument [Line Items]
Long-term debt stated interest rate	6.60%
Make Whole Premium Additional Percent	0.00%
Debt Instrument, Face Amount	$ 100.0