Fair value measurements (Tables)

12 Months Ended

Dec. 31, 2017

Fair Value Disclosures [Abstract]

GMIB Annuitization Experience [Table Text Block]

% of total GMIB guaranteed value	Year of GMIB eligibility	Maximum annuitization rate(s) (per year)	Maximum annuitization rates based on
67%	First year	2% - 52%	Actual Experience
	Subsequent years	1% - 100%
3%	First year	N/A	N/A (1)
	Subsequent years	12%, 100%	Weighted average(2)
30%	First year	25%, 56%	Weighted average(2)
	Subsequent years	12%, 36%

⁽¹⁾ Because all policies in this bracket are past the first year of eligibility, first year annuitization assumptions are no longer modeled.

⁽²⁾ Weighted average of two different annuitization rates

Financial Instruments Measured At Fair Value On A Recurring Basis

Financial instruments measured at fair value on a recurring basis, by valuation hierarchy 

December 31, 2017	Level 1		Level 2		Level 3		Total
(in millions of U.S. dollars)
Assets:
Fixed maturities available for sale
U.S. Treasury and agency	$	3,129	$	569	$	—	$	3,698
Foreign	—		20,937		93		21,030
Corporate securities	—		22,959		1,037		23,996
Mortgage-backed securities	—		15,212		78		15,290
States, municipalities, and political subdivisions	—		14,925		—		14,925
	3,129		74,602		1,208		78,939
Equity securities	893		—		44		937
Short-term investments	2,309		1,252		—		3,561
Other investments (1)	466		305		263		1,034
Securities lending collateral	—		1,737		—		1,737
Investment derivative instruments	18		—		—		18
Other derivative instruments	1		—		—		1
Separate account assets	2,635		99		—		2,734
Total assets measured at fair value (1)	$	9,451	$	77,995	$	1,515	$	88,961
Liabilities:
Investment derivative instruments	$	30	$	—	$	—	$	30
Other derivative instruments	21		—		2		23
GLB (2)	—		—		204		204
Total liabilities measured at fair value	$	51	$	—	$	206	$	257

⁽¹⁾  Excluded from the table above are partially-owned investments, investment funds, and limited partnerships of $3,623 million and other investments of $15 million at December 31, 2017 measured using NAV as a practical expedient.

⁽²⁾  Our GLB reinsurance product meets the definition of a derivative instrument for accounting purposes and is accordingly carried at fair value. Excluded from the table above is the portion of the GLB derivative liability classified as Future policy benefits in the Consolidated balance sheets. Refer to Note 5c) for additional information.

December 31, 2016	Level 1		Level 2		Level 3		Total
(in millions of U.S. dollars)
Assets:
Fixed maturities available for sale
U.S. Treasury and agency	$	2,175	$	695	$	—	$	2,870
Foreign	—		21,366		74		21,440
Corporate securities	—		23,468		681		24,149
Mortgage-backed securities	—		13,962		45		14,007
States, municipalities, and political subdivisions	—		17,649		—		17,649
	2,175		77,140		800		80,115
Equity securities	773		—		41		814
Short-term investments	1,757		1,220		25		3,002
Other investments (1)	384		259		225		868
Securities lending collateral	—		1,092		—		1,092
Investment derivative instruments	31		—		—		31
Other derivative instruments	3		—		—		3
Separate account assets	1,784		95		—		1,879
Total assets measured at fair value (1)	$	6,907	$	79,806	$	1,091	$	87,804
Liabilities:
Investment derivative instruments	$	54	$	—	$	—	$	54
Other derivative instruments	—		—		13		13
GLB (2)	—		—		559		559
Total liabilities measured at fair value	$	54	$	—	$	572	$	626

⁽¹⁾  Excluded from the table above are partially-owned investments, investment funds, and limited partnerships of $3,626 million and other investments of $25 million at December 31, 2016 measured using NAV as a practical expedient.

⁽²⁾  Our GLB reinsurance product meets the definition of a derivative instrument for accounting purposes and is accordingly carried at fair value. Excluded from the table above is the portion of the GLB derivative liability classified as Future policy benefits in the Consolidated balance sheets. Refer to Note 5c) for additional information.

Fair Value And Maximum Future Funding Commitments Related To Investments

The following table presents, by investment category, the expected liquidation period, fair value, and maximum future funding commitments of alternative investments: 

		December 31				December 31
		2017				2016
(in millions of U.S. dollars)	Expected Liquidation Period of Underlying Assets	Fair Value		Maximum Future Funding Commitments		Fair Value		Maximum Future Funding Commitments
Financial	5 to 9 Years	$	540	$	330	$	548	$	428
Real Assets	3 to 7 Years	651		114		536		230
Distressed	3 to 7 Years	289		141		485		179
Private Credit	3 to 7 Years	187		327		236		259
Traditional	3 to 15 Years	1,656		3,149		1,550		930
Vintage	1 to 2 Years	30		—		21		14
Investment funds	Not Applicable	270		—		251		—
		$	3,623	$	4,061	$	3,627	$	2,040

Schedule Of Significant Unobservable Inputs Used In Level 3 Liability Valuations

The following table presents the significant unobservable inputs used in the Level 3 liability valuations. Excluded from the table below are inputs used to determine the fair value of Level 3 assets which are based on single broker quotes and contain no quantitative unobservable inputs developed by management.

(in millions of U.S. dollars, except for percentages)	Fair Value at December 31, 2017		Valuation Technique	Significant Unobservable Inputs	Ranges
GLB(1)	$	204	Actuarial model	Lapse rate	3% – 33%
				Annuitization rate	0% – 100%

⁽¹⁾  Discussion of the most significant inputs used in the fair value measurement of GLB and the sensitivity of those assumptions is included within Note 4 a) Guaranteed living benefits.

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation

The following tables present a reconciliation of the beginning and ending balances of financial instruments measured at fair value using significant unobservable inputs (Level 3): 

																Assets						Liabilities
	Available-for-Sale Debt Securities									Equity securities			Short-term investments			Other investments			Other derivative instruments			GLB(2)
Year Ended December 31, 2017	Foreign			Corporate securities (1)			MBS
(in millions of U.S. dollars)
Balance, beginning of year	$	74		$	681		$	45		$	41		$	25		$	225		$	13		$	559
Transfers into Level 3	—			231			50			—			—			—			—			9
Transfers out of Level 3	(3		)	(93		)	—			—			—			—			(9		)	—
Change in Net Unrealized Gains (Losses) included in OCI	3			(12		)	—			(1		)	—			6			—			—
Net Realized Gains/Losses	—			—			—			2			—			—			(2		)	(364		)
Purchases	84			521			8			24			16			56			—			—
Sales	(59		)	(111		)	(1		)	(22		)	—			—			—			—
Settlements	(6		)	(180		)	(24		)	—			(41		)	(24		)	—			—
Balance, end of year	$	93		$	1,037		$	78		$	44		$	—		$	263		$	2		$	204
Net Realized Gains/Losses Attributable to Changes in Fair Value at the Balance Sheet Date	$	(1	)	$	(2	)	$	—		$	(1	)	$	—		$	—		$	(2	)	$	(364	)

⁽¹⁾  Transfers into and Purchases in Level 3 primarily consist of privately-placed fixed income securities.

⁽²⁾  Our GLB reinsurance product meets the definition of a derivative instrument for accounting purposes and is accordingly carried at fair value. Excluded from the table above is the portion of the GLB derivative liability classified as Future policy benefits in the Consolidated balance sheets. Refer to Note 5c) for additional information.

																						Liabilities
	Available-for-Sale Debt Securities									Equity securities			Short-term investments			Other investments				Other derivative instruments		GLB(1)
Year Ended December 31, 2016	Foreign			Corporate securities			MBS
(in millions of U.S. dollars)
Balance, beginning of year	$	57		$	174		$	53		$	16		$	—		$	212		—	$	6	$	609
Transfers into Level 3	9			53			—			—			—			—			—	—		—
Transfers out of Level 3	(24		)	(10		)	—			—			(50		)	—				—		—
Change in Net Unrealized Gains (Losses) included in OCI	1			15			(1		)	2			—			(2		)		—		—
Net Realized Gains/Losses	(6		)	(13		)	—			1			—			1				5		(50		)
Purchases (2)	70			566			1			27			75			33				2		—
Sales	(17		)	(59		)	(8		)	(5		)	—			—				—		—
Settlements	(16		)	(45		)	—			—			—			(19		)		—		—
Balance, end of year	$	74		$	681		$	45		$	41		$	25		$	225			$	13	$	559
Net Realized Gains/Losses Attributable to Changes in Fair Value at the Balance Sheet Date	$	(5	)	$	(11	)	$	—		$	—		$	—		$	1			$	5	$	(50	)

⁽¹⁾  Our GLB reinsurance product meets the definition of a derivative instrument for accounting purposes and is accordingly carried at fair value. Excluded from the table above is the portion of the GLB derivative liability classified as Future policy benefits in the Consolidated balance sheets. The liability for GLB reinsurance was $853 million at December 31, 2016 and $888 million at December 31, 2015, which includes a fair value derivative adjustment of $559 million and $609 million, respectively. 

⁽²⁾ Includes acquired invested assets as a result of the Chubb Corp acquisition.

	Assets															Liabilities
	Available-for-Sale Debt Securities															Other derivative instruments		GLB(1)
Year Ended December 31, 2015	Foreign			Corporate securities			MBS			Equity securities			Other investments
(in millions of U.S. dollars)
Balance, beginning of year	$	22		$	187		$	15		$	2		$	204		$	4	$	406
Transfers into Level 3	34			16			—			—			—			—		—
Transfers out of Level 3	—			—			—			—			—			—		—
Change in Net Unrealized Gains (Losses) included in OCI	(2		)	(1		)	—			3			(6		)	—		—
Net Realized Gains/Losses	(1		)	(4		)	—			(2		)	—			2		203
Purchases	15			52			41			13			33			—		—
Sales	(3		)	(28		)	(2		)	—			—			—		—
Settlements	(8		)	(48		)	(1		)				(19		)	—
Balance, end of year	$	57		$	174		$	53		$	16		$	212		$	6	$	609
Net Realized Gains/Losses Attributable to Changes in Fair Value at the Balance Sheet Date	$	(1	)	$	(2	)	$	—		$	(2	)	$	—		$	2	$	203

⁽¹⁾  Our GLB reinsurance product meets the definition of a derivative instrument for accounting purposes and is accordingly carried at fair value. Excluded from the table above is the portion of the GLB derivative liability classified as Future policy benefits in the Consolidated balance sheets. The liability for GLB reinsurance was $888 million at December 31, 2015 and $663 million at December 31, 2014, which includes a fair value derivative adjustment of $609 million and $406 million, respectively. 

Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]

																Assets						Liabilities
	Available-for-Sale Debt Securities									Equity securities			Short-term investments			Other investments			Other derivative instruments			GLB(2)
Year Ended December 31, 2017	Foreign			Corporate securities (1)			MBS
(in millions of U.S. dollars)
Balance, beginning of year	$	74		$	681		$	45		$	41		$	25		$	225		$	13		$	559
Transfers into Level 3	—			231			50			—			—			—			—			9
Transfers out of Level 3	(3		)	(93		)	—			—			—			—			(9		)	—
Change in Net Unrealized Gains (Losses) included in OCI	3			(12		)	—			(1		)	—			6			—			—
Net Realized Gains/Losses	—			—			—			2			—			—			(2		)	(364		)
Purchases	84			521			8			24			16			56			—			—
Sales	(59		)	(111		)	(1		)	(22		)	—			—			—			—
Settlements	(6		)	(180		)	(24		)	—			(41		)	(24		)	—			—
Balance, end of year	$	93		$	1,037		$	78		$	44		$	—		$	263		$	2		$	204
Net Realized Gains/Losses Attributable to Changes in Fair Value at the Balance Sheet Date	$	(1	)	$	(2	)	$	—		$	(1	)	$	—		$	—		$	(2	)	$	(364	)

⁽¹⁾  Transfers into and Purchases in Level 3 primarily consist of privately-placed fixed income securities.

⁽²⁾  Our GLB reinsurance product meets the definition of a derivative instrument for accounting purposes and is accordingly carried at fair value. Excluded from the table above is the portion of the GLB derivative liability classified as Future policy benefits in the Consolidated balance sheets. Refer to Note 5c) for additional information.

																						Liabilities
	Available-for-Sale Debt Securities									Equity securities			Short-term investments			Other investments				Other derivative instruments		GLB(1)
Year Ended December 31, 2016	Foreign			Corporate securities			MBS
(in millions of U.S. dollars)
Balance, beginning of year	$	57		$	174		$	53		$	16		$	—		$	212		—	$	6	$	609
Transfers into Level 3	9			53			—			—			—			—			—	—		—
Transfers out of Level 3	(24		)	(10		)	—			—			(50		)	—				—		—
Change in Net Unrealized Gains (Losses) included in OCI	1			15			(1		)	2			—			(2		)		—		—
Net Realized Gains/Losses	(6		)	(13		)	—			1			—			1				5		(50		)
Purchases (2)	70			566			1			27			75			33				2		—
Sales	(17		)	(59		)	(8		)	(5		)	—			—				—		—
Settlements	(16		)	(45		)	—			—			—			(19		)		—		—
Balance, end of year	$	74		$	681		$	45		$	41		$	25		$	225			$	13	$	559
Net Realized Gains/Losses Attributable to Changes in Fair Value at the Balance Sheet Date	$	(5	)	$	(11	)	$	—		$	—		$	—		$	1			$	5	$	(50	)

⁽¹⁾  Our GLB reinsurance product meets the definition of a derivative instrument for accounting purposes and is accordingly carried at fair value. Excluded from the table above is the portion of the GLB derivative liability classified as Future policy benefits in the Consolidated balance sheets. The liability for GLB reinsurance was $853 million at December 31, 2016 and $888 million at December 31, 2015, which includes a fair value derivative adjustment of $559 million and $609 million, respectively. 

⁽²⁾ Includes acquired invested assets as a result of the Chubb Corp acquisition.

	Assets															Liabilities
	Available-for-Sale Debt Securities															Other derivative instruments		GLB(1)
Year Ended December 31, 2015	Foreign			Corporate securities			MBS			Equity securities			Other investments
(in millions of U.S. dollars)
Balance, beginning of year	$	22		$	187		$	15		$	2		$	204		$	4	$	406
Transfers into Level 3	34			16			—			—			—			—		—
Transfers out of Level 3	—			—			—			—			—			—		—
Change in Net Unrealized Gains (Losses) included in OCI	(2		)	(1		)	—			3			(6		)	—		—
Net Realized Gains/Losses	(1		)	(4		)	—			(2		)	—			2		203
Purchases	15			52			41			13			33			—		—
Sales	(3		)	(28		)	(2		)	—			—			—		—
Settlements	(8		)	(48		)	(1		)				(19		)	—
Balance, end of year	$	57		$	174		$	53		$	16		$	212		$	6	$	609
Net Realized Gains/Losses Attributable to Changes in Fair Value at the Balance Sheet Date	$	(1	)	$	(2	)	$	—		$	(2	)	$	—		$	2	$	203

⁽¹⁾  Our GLB reinsurance product meets the definition of a derivative instrument for accounting purposes and is accordingly carried at fair value. Excluded from the table above is the portion of the GLB derivative liability classified as Future policy benefits in the Consolidated balance sheets. The liability for GLB reinsurance was $888 million at December 31, 2015 and $663 million at December 31, 2014, which includes a fair value derivative adjustment of $609 million and $406 million, respectively. 

Carrying Values And Fair Values Of Financial Instruments Not Measured At Fair Value

December 31, 2017	Fair Value								Carrying Value
(in millions of U.S. dollars)	Level 1		Level 2		Level 3		Total
Assets:
Fixed maturities held to maturity
U.S. Treasury and agency	$	857	$	58	$	—	$	915	$	908
Foreign	—		1,757		—		1,757		1,738
Corporate securities	—		3,184		35		3,219		3,159
Mortgage-backed securities	—		2,742		—		2,742		2,724
States, municipalities, and political subdivisions	—		5,841		—		5,841		5,806
Total assets	$	857	$	13,582	$	35	$	14,474	$	14,335
Liabilities:
Repurchase agreements	$	—	$	1,408	$	—	$	1,408	$	1,408
Short-term debt	—		1,013		—		1,013		1,013
Long-term debt	—		12,332		—		12,332		11,556
Trust preferred securities	—		468		—		468		308
Total liabilities	$	—	$	15,221	$	—	$	15,221	$	14,285

December 31, 2016	Fair Value								Carrying Value
(in millions of U.S. dollars)	Level 1		Level 2		Level 3		Total
Assets:
Fixed maturities held to maturity
U.S. Treasury and agency	$	555	$	106	$	—	$	661	$	655
Foreign	—		667		—		667		640
Corporate securities	—		2,782		13		2,795		2,771
Mortgage-backed securities	—		1,428		—		1,428		1,393
States, municipalities, and political subdivisions	—		5,119		—		5,119		5,185
Total assets	$	555	$	10,102	$	13	$	10,670	$	10,644
Liabilities:
Repurchase agreements	$	—	$	1,403	$	—	$	1,403	$	1,403
Short-term debt	—		503		—		503		500
Long-term debt	—		12,998		—		12,998		12,610
Trust preferred securities	—		456		—		456		308
Total liabilities	$	—	$	15,360	$	—	$	15,360	$	14,821