Short-Term and Long-Term Debt - Narrative (Details) - USD ($)	1 Months Ended	12 Months Ended
	Aug. 31, 2020	Dec. 31, 2023
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 3,835,000,000
Non-operating indebtedness of subsidiaries to total capitalization, maximum		7.50%
Delaware Trust Facility
Debt Instrument [Line Items]
Stockholders' equity threshold triggering required facility exercise		$ 2,750,000,000
Five-year revolving credit facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		2,000,000,000
Banking regulation, mortgage banking, net worth, minimum		$ 8,626,000,000
Percentage of aggregate net proceeds of equity issuances		50.00%
Debt to capital ratio (low end of range)		35.00%
Debt to capital ratio (high end of range)		100.00%
Delaware Trust Facility
Debt Instrument [Line Items]
Facility agreement term	10 years
Pre-capitalized securities, sold by trust	$ 500,000,000
Line of credit facility, commitment fee percentage		1.691%
Delaware Trust Facility | Senior Notes 2.330%, Due 2030
Debt Instrument [Line Items]
Debt instrument, face amount		$ 500,000,000
Debt instrument, interest rate, stated percentage		2.33%