Investments (Tables)

3 Months Ended

Mar. 31, 2018

Investments, Debt and Equity Securities [Abstract]

Schedule Of Amortized Cost And Fair Value Of HTM Fixed Maturities And Related OTTI Recognized In AOCI

March 31, 2018	Amortized Cost		Gross Unrealized Appreciation		Gross Unrealized Depreciation			Fair Value		OTTI Recognized in AOCI
(in millions of U.S. dollars)
Available for sale
U.S. Treasury and agency	$	3,893	$	22	$	(77	)	$	3,838	$	—
Foreign	21,705		513		(187		)	22,031		—
Corporate securities	23,509		332		(274		)	23,567		(4		)
Mortgage-backed securities	16,116		53		(349		)	15,820		(1		)
States, municipalities, and political subdivisions	13,985		61		(191		)	13,855		—
	$	79,208	$	981	$	(1,078	)	$	79,111	$	(5	)
Held to maturity
U.S. Treasury and agency	$	1,037	$	9	$	(14	)	$	1,032	$	—
Foreign	1,754		17		(20		)	1,751		—
Corporate securities	3,026		26		(55		)	2,997		—
Mortgage-backed securities	2,681		11		(45		)	2,647		—
States, municipalities, and political subdivisions	5,755		18		(78		)	5,695		—
	$	14,253	$	81	$	(212	)	$	14,122	$	—

December 31, 2017	Amortized Cost		Gross Unrealized Appreciation		Gross Unrealized Depreciation			Fair Value		OTTI Recognized in AOCI
(in millions of U.S. dollars)
Available for sale
U.S. Treasury and agency	$	3,701	$	32	$	(35	)	$	3,698	$	—
Foreign	20,514		622		(106		)	21,030		(1		)
Corporate securities	23,453		638		(95		)	23,996		(4		)
Mortgage-backed securities	15,279		111		(100		)	15,290		(1		)
States, municipalities, and political subdivisions	14,888		125		(88		)	14,925		—
	$	77,835	$	1,528	$	(424	)	$	78,939	$	(6	)
Held to maturity
U.S. Treasury and agency	$	908	$	12	$	(5	)	$	915	$	—
Foreign	1,738		27		(8		)	1,757		—
Corporate securities	3,159		67		(7		)	3,219		—
Mortgage-backed securities	2,724		23		(5		)	2,742		—
States, municipalities, and political subdivisions	5,806		50		(15		)	5,841		—
	$	14,335	$	179	$	(40	)	$	14,474	$	—

Schedule Of Amortized Cost and Fair Value of Available-for-sale Securities and Related OTTI Recognized in AOCI

March 31, 2018	Amortized Cost		Gross Unrealized Appreciation		Gross Unrealized Depreciation			Fair Value		OTTI Recognized in AOCI
(in millions of U.S. dollars)
Available for sale
U.S. Treasury and agency	$	3,893	$	22	$	(77	)	$	3,838	$	—
Foreign	21,705		513		(187		)	22,031		—
Corporate securities	23,509		332		(274		)	23,567		(4		)
Mortgage-backed securities	16,116		53		(349		)	15,820		(1		)
States, municipalities, and political subdivisions	13,985		61		(191		)	13,855		—
	$	79,208	$	981	$	(1,078	)	$	79,111	$	(5	)
Held to maturity
U.S. Treasury and agency	$	1,037	$	9	$	(14	)	$	1,032	$	—
Foreign	1,754		17		(20		)	1,751		—
Corporate securities	3,026		26		(55		)	2,997		—
Mortgage-backed securities	2,681		11		(45		)	2,647		—
States, municipalities, and political subdivisions	5,755		18		(78		)	5,695		—
	$	14,253	$	81	$	(212	)	$	14,122	$	—

December 31, 2017	Amortized Cost		Gross Unrealized Appreciation		Gross Unrealized Depreciation			Fair Value		OTTI Recognized in AOCI
(in millions of U.S. dollars)
Available for sale
U.S. Treasury and agency	$	3,701	$	32	$	(35	)	$	3,698	$	—
Foreign	20,514		622		(106		)	21,030		(1		)
Corporate securities	23,453		638		(95		)	23,996		(4		)
Mortgage-backed securities	15,279		111		(100		)	15,290		(1		)
States, municipalities, and political subdivisions	14,888		125		(88		)	14,925		—
	$	77,835	$	1,528	$	(424	)	$	78,939	$	(6	)
Held to maturity
U.S. Treasury and agency	$	908	$	12	$	(5	)	$	915	$	—
Foreign	1,738		27		(8		)	1,757		—
Corporate securities	3,159		67		(7		)	3,219		—
Mortgage-backed securities	2,724		23		(5		)	2,742		—
States, municipalities, and political subdivisions	5,806		50		(15		)	5,841		—
	$	14,335	$	179	$	(40	)	$	14,474	$	—

Schedule Of Fixed Maturities By Contractual Maturity

The following table presents fixed maturities by contractual maturity:

			March 31				December 31
			2018				2017
(in millions of U.S. dollars)	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Available for sale
Due in 1 year or less	$	3,735	$	3,746	$	3,164	$	3,182
Due after 1 year through 5 years	25,140		25,251		24,749		25,068
Due after 5 years through 10 years	25,243		25,097		25,388		25,704
Due after 10 years	8,974		9,197		9,255		9,695
	63,092		63,291		62,556		63,649
Mortgage-backed securities	16,116		15,820		15,279		15,290
	$	79,208	$	79,111	$	77,835	$	78,939
Held to maturity
Due in 1 year or less	$	838	$	840	$	743	$	746
Due after 1 year through 5 years	2,684		2,678		2,669		2,688
Due after 5 years through 10 years	4,713		4,635		4,744		4,756
Due after 10 years	3,337		3,322		3,455		3,542
	11,572		11,475		11,611		11,732
Mortgage-backed securities	2,681		2,647		2,724		2,742
	$	14,253	$	14,122	$	14,335	$	14,474

Schedule of Realized Gain (Loss)

The following table presents the components of Net realized gains (losses):

	Three Months Ended
	March 31
(in millions of U.S. dollars)	2018			2017
Fixed maturities:
OTTI on fixed maturities, gross	$	(1	)	$	(6	)
OTTI on fixed maturities recognized in OCI (pre-tax)	—			—
OTTI on fixed maturities, net	(1		)	(6		)
Gross realized gains excluding OTTI	66			34
Gross realized losses excluding OTTI	(88		)	(40		)
Total fixed maturities	(23		)	(12		)
Equity securities:
OTTI on equity securities	—			(5		)
Gross realized gains excluding OTTI	10			9
Gross realized losses excluding OTTI	(21		)	—
Total equity securities	(11		)	4
OTTI on other investments	—			(8		)
Other investments	29			—
Foreign exchange losses	(77		)	(19		)
Investment and embedded derivative instruments	17			6
Fair value adjustments on insurance derivative	38			93
S&P put options and futures	22			(74		)
Other derivative instruments	2			2
Other	1			1
Net realized gains (losses)	$	(2	)	$	(7	)

Schedule Of Roll-Forward Of Pre-Tax Credit Losses Related To Fixed Maturities For Which A Portion Of OTTI Was Recognized In OCI

The following table presents a roll-forward of pre-tax credit losses related to fixed maturities for which a portion of OTTI was recognized in OCI:

	Three Months Ended
	March 31
(in millions of U.S. dollars)	2018			2017
Balance of credit losses related to securities still held – beginning of period	$	22		$	35
Additions where no OTTI was previously recorded	—			—
Additions where an OTTI was previously recorded	—			1
Reductions for securities sold during the period	(7		)	(4		)
Balance of credit losses related to securities still held – end of period	$	15		$	32

Gain (Loss) on Investments [Table Text Block]

Effective January 1, 2018, we adopted new accounting guidance that requires any changes in fair value of equity securities and other investments that are accounted for under the cost-method to be recognized immediately in realized gains and losses in net income. As a result, beginning on January 1, 2018, realized gains and losses from these investments include both sales of securities and unrealized gains and losses as follows:

	Three Months Ended
	March 31, 2018
(in millions of U.S. dollars)	Equity Securities			Other Investments
Net gains (losses) recognized during the period	$	(11	)	$	29
Less: Net gains (losses) recognized from sales of securities	10			—
Unrealized gains (losses) recognized for securities still held at reporting date	$	(21	)	$	29

Schedule Of Aggregate Fair Value And Gross Unrealized Loss By Length Of Time The Security Has Continuously Been In An Unrealized Loss Position

The following tables present, for all securities in an unrealized loss position (including securities on loan), the aggregate fair value and gross unrealized loss by length of time the security has continuously been in an unrealized loss position:

	0 – 12 Months					Over 12 Months					Total
March 31, 2018	Fair Value		Gross Unrealized Loss			Fair Value		Gross Unrealized Loss			Fair Value		Gross Unrealized Loss
(in millions of U.S. dollars)
U.S. Treasury and agency	$	2,869	$	(55	)	$	1,314	$	(36	)	$	4,183	$	(91	)
Foreign	8,715		(155		)	1,643		(52		)	10,358		(207		)
Corporate securities	12,355		(260		)	1,501		(69		)	13,856		(329		)
Mortgage-backed securities	12,313		(257		)	3,033		(137		)	15,346		(394		)
States, municipalities, and political subdivisions	15,030		(218		)	1,343		(51		)	16,373		(269		)
Total fixed maturities	$	51,282	$	(945	)	$	8,834	$	(345	)	$	60,116	$	(1,290	)

	0 – 12 Months					Over 12 Months					Total
December 31, 2017	Fair Value		Gross Unrealized Loss			Fair Value		Gross Unrealized Loss			Fair Value		Gross Unrealized Loss
(in millions of U.S. dollars)
U.S. Treasury and agency	$	2,172	$	(14	)	$	1,249	$	(26	)	$	3,421	$	(40	)
Foreign	5,657		(65		)	1,693		(49		)	7,350		(114		)
Corporate securities	5,210		(56		)	1,332		(46		)	6,542		(102		)
Mortgage-backed securities	6,194		(31		)	3,209		(74		)	9,403		(105		)
States, municipalities, and political subdivisions	9,259		(71		)	1,402		(32		)	10,661		(103		)
Total fixed maturities	28,492		(237		)	8,885		(227		)	37,377		(464		)
Equity securities	115		(12		)	—		—			115		(12		)
Other investments	78		(8		)	—		—			78		(8		)
Total	$	28,685	$	(257	)	$	8,885	$	(227	)	$	37,570	$	(484	)

Schedule Of Components Of Restricted Assets

The following table presents the components of restricted assets:

	March 31		December 31
(in millions of U.S. dollars)	2018		2017
Trust funds	$	17,029	$	17,011
Deposits with U.S. regulatory authorities	2,463		2,345
Deposits with non-U.S. regulatory authorities	2,290		2,250
Assets pledged under repurchase agreements	1,460		1,434
Other pledged assets	433		414
	$	23,675	$	23,454