Statutory Financial Data and Restrictions - Schedule of Statutory Financial Data and Restrictions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
General Insurance
Statutory Accounting Practices [Line Items]
Statutory net income (loss)	$ 3,779	$ 3,319	$ 4,222
Statutory capital and surplus	30,230	33,476
Aggregate minimum required statutory capital and surplus	9,666	10,994
General Insurance | Domestic
Statutory Accounting Practices [Line Items]
Statutory net income (loss)	1,912	2,272	2,649
Statutory capital and surplus	18,703	19,563
Aggregate minimum required statutory capital and surplus	3,625	3,680
General Insurance | Foreign
Statutory Accounting Practices [Line Items]
Statutory net income (loss)	1,867	1,047	1,573
Statutory capital and surplus	11,527	13,913
Aggregate minimum required statutory capital and surplus	6,041	7,314
Life Insurance Companies
Statutory Accounting Practices [Line Items]
Statutory net income (loss)	3,303	3,096	2,593
Statutory capital and surplus	15,219	12,715
Aggregate minimum required statutory capital and surplus	4,248	4,251
Life Insurance Companies | Domestic
Statutory Accounting Practices [Line Items]
Statutory net income (loss)	3,354	3,091	2,588
Statutory capital and surplus	14,752	12,229
Aggregate minimum required statutory capital and surplus	4,025	4,057
Life Insurance Companies | Foreign
Statutory Accounting Practices [Line Items]
Statutory net income (loss)	(51)	5	$ 5
Statutory capital and surplus	467	486
Aggregate minimum required statutory capital and surplus	$ 223	$ 194