Held-For-Sale Classification - Schedule of Disposal Groups (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Assets:
Assets held for sale	$ 12,695	$ 0
Liabilities:
Liabilities held for sale	9,595	$ 0
Assets held-for-sale
Assets:
Bonds available for sale	4,568
Other invested assets	5
Restricted cash included in short-term investments	46
Short-term investments, including restricted cash of	418
Cash	191
Accrued investment income	26
Premiums and other receivables, net of allowance for credit losses and disputes	3,863
Reinsurance assets - other, net of allowance for credit losses and disputes	2,057
Deferred income taxes	75
Deferred policy acquisition costs	712
Other assets, net of allowance for credit losses(a)	780
Assets held for sale	12,695
Liabilities:
Liability for unpaid losses and loss adjustment expenses, including allowance for credit losses	4,929
Unearned premiums	3,006
Other liabilities	1,393
Long-term debt	267
Liabilities held for sale	9,595
Validus Re | Assets held-for-sale
Assets:
Bonds available for sale	4,568
Other invested assets	5
Short-term investments, including restricted cash of	389
Cash	191
Accrued investment income	26
Premiums and other receivables, net of allowance for credit losses and disputes	3,812
Reinsurance assets - other, net of allowance for credit losses and disputes	2,057
Deferred income taxes	75
Deferred policy acquisition costs	712
Other assets, net of allowance for credit losses(a)	591
Assets held for sale	12,426
Liabilities:
Liability for unpaid losses and loss adjustment expenses, including allowance for credit losses	4,929
Unearned premiums	3,006
Other liabilities	1,220
Long-term debt	267
Liabilities held for sale	9,422
Goodwill	318
Intangible assets	235
CRS | Assets held-for-sale
Assets:
Bonds available for sale	0
Other invested assets	0
Short-term investments, including restricted cash of	29
Cash	0
Accrued investment income	0
Premiums and other receivables, net of allowance for credit losses and disputes	51
Reinsurance assets - other, net of allowance for credit losses and disputes	0
Deferred income taxes	0
Deferred policy acquisition costs	0
Other assets, net of allowance for credit losses(a)	189
Assets held for sale	269
Liabilities:
Liability for unpaid losses and loss adjustment expenses, including allowance for credit losses	0
Unearned premiums	0
Other liabilities	173
Long-term debt	0
Liabilities held for sale	173
Goodwill	23
Intangible assets	$ 20