Summary of significant accounting policies Summary of Significant Accounting Policies (Tables) (Tables)

12 Months Ended

Dec. 31, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Accounting Standards Update and Change in Accounting Principle

The impact of adoption of the new guidance on our historical financial statements is as follows:

	December 31, 2022
(in millions of U.S. dollars)	As Previously Reported		LDTI Adoption Adjustment		As Adjusted
Consolidated balance sheet
Reinsurance recoverable on losses and loss expenses	$	18,901	$	(42)	$	18,859
Reinsurance recoverable on policy benefits	303		(1)		302
Deferred policy acquisition costs	5,788		243		6,031
Value of business acquired	3,596		106		3,702
Prepaid reinsurance premiums	3,140		(4)		3,136
Investments in partially-owned insurance companies	2,877		(370)		2,507
Unpaid losses and loss expenses	76,323		(576)		75,747
Unearned premiums	20,360		(647)		19,713
Future policy benefits	10,120		356		10,476
Market risk benefits	—		800		800
Insurance and reinsurance balances payable	7,795		(15)		7,780
Deferred tax liabilities	292		85		377
Retained earnings	48,334		(29)		48,305
Accumulated other comprehensive income (loss)	(10,193)		8		(10,185)

Excluded from the table above is the reclassification of Separate account assets, Separate account liabilities, and Policyholders' account balances as separate line items on the Consolidated balance sheets. Separate accounts assets were previously classified in Other assets, and Separate account liabilities and Policyholders' account balances were previously classified in Accounts payable, accrued expenses, and other liabilities.

	Twelve Months Ended						Twelve Months Ended
	December 31, 2022						December 31, 2021
(in millions of U.S. dollars)	As Previously Reported		LDTI Adoption Adjustment		As Adjusted		As Previously Reported		LDTI Adoption Adjustment		As Adjusted
Consolidated statements of operations and comprehensive income
Net premiums written	$	41,755	$	(35)	$	41,720	$	37,868	$	(41)	$	37,827
Net premiums earned	40,389		(29)		40,360		36,355		(63)		36,292
Net realized gains (losses)	(965)		(120)		(1,085)		1,152		(122)		1,030
Market risk benefits gains (losses)	—		80		80		—		91		91
Losses and loss expenses	23,342		(770)		22,572		21,980		(950)		21,030
Policy benefits	1,492		822		2,314		699		1,041		1,740
Policy acquisition costs	7,392		(53)		7,339		6,918		(160)		6,758
Other (income) expense	74		15		89		(2,365)		(2)		(2,367)
Income tax expense	1,255		(16)		1,239		1,277		(8)		1,269
Net Income	5,313		(67)		5,246		8,539		(14)		8,525
Other comprehensive income
Change in current discount rate on future policy benefits	—		1,480		1,480		—		387		387
Change in instrument-specific credit risk on market risk benefits	—		33		33		—		27		27
Income tax benefit related to OCI items	1,121		(156)		965		427		(61)		366
Comprehensive income (loss)	(5,230)		1,365		(3,865)		6,020		364		6,384

	Twelve Months Ended						Twelve Months Ended
	December 31, 2022						December 31, 2021
(in millions of U.S. dollars)	As Previously Reported		LDTI Adoption Adjustment		As Adjusted		As Previously Reported		LDTI Adoption Adjustment		As Adjusted
Consolidated statements of cash flows
Net cash flows from operating activities	$	11,243	$	15	$	11,258	$	11,149	$	2	$	11,151
Net cash flows used for financing activities	(5,127)		(15)		(5,142)		(4,409)		(2)		(4,411)

The following table presents a reconciliation of the pre-adoption December 31, 2020, to the post adoption January 1, 2021, balance of future policy benefits:

	Life Insurance								Overseas General Insurance				Offsetting Equity Line Classification
(in millions of U.S. dollars)	Term Life		Whole Life		A&H		Other		A&H		Total
Future policy benefits
Balance – December 31, 2020 (1)	$	391	$	2,578	$	2,270	$	72	$	754	$	6,065
Effect of change in current discount rate	63		1,189		299		17		19		1,587		AOCI
Balance – January 1, 2021	$	454	$	3,767	$	2,569	$	89	$	773	$	7,652

(1)     Includes future policy benefits previously included within Unpaid losses and loss expenses on the pre-adoption Consolidated balance sheets, primarily certain international A&H business, and excludes deferred profit liability and certain guaranteed minimum death benefits reclassified to Market risk benefits on the post adoption period balance sheets.

The following table presents a reconciliation of the pre-adoption December 31, 2020, to the post adoption January 1, 2021, balance of market risk benefits:

(in millions of U.S. dollars)			Offsetting Equity Line Classification
Market risk benefits
Balance – December 31, 2020	$	1,138
Cumulative effect of changes in instrument-specific credit risk between original contract issuance date and transition date (1)	84		AOCI
Other fair value adjustments	(59)		Retained Earnings
Balance – January 1, 2021	$	1,163

(1)     Includes $77 million of instrument-specific credit risk allocated from retained earnings to AOCI.