Common Stock ($0.01 par value) Common Stock [Member] Entity Tax Identification Number Entity Tax Identification Number Four Point Two Junior Subordinated Notes Due 2061 Four Point Two Junior Subordinated Notes Due 2061 [Member] Four Point Two Junior Subordinated Notes Due 2061 Entity File Number Entity File Number Cover [Abstract] Cover [Abstract] Title of 12(b) Security Title of 12(b) Security Entities [Table] Entities [Table] Local Phone Number Local Phone Number Class of Stock [Domain] Class of Stock [Domain] Soliciting Material Soliciting Material Entity Address, Address Line One Entity Address, Address Line One Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name Entity Address, State or Province Entity Address, State or Province Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code 5.875% Junior Subordinated Notes due 2059 Five Point Eight Seventy Five Junior Subordinated Notes Due 2059 [Member] Five Point Eight Seventy Five Junior Subordinated Notes Due 2059 Written Communications Written Communications Entity Information [Line Items] Entity Information [Line Items] Trading Symbol Trading Symbol City Area Code City Area Code Four Point Seventy Five Junior Subordinated Notes Due 2060 Four Point Seventy Five Junior Subordinated Notes Due 2060 [Member] Four Point Seventy Five Junior Subordinated Notes Due 2060 Document Period End Date Document Period End Date Amendment Flag Amendment Flag Pre-commencement Issuer Tender Offer Pre-commencement Issuer Tender Offer Entity Address, City or Town Entity Address, City or Town Six Point Seventy Five Junior Subordinated Notes Due 2064 Six Point Seventy Five Junior Subordinated Notes Due 2064 [Member] Six Point Seventy Five Junior Subordinated Notes Due 2064 Security Exchange Name Security Exchange Name Document Type Document Type Class of Stock [Axis] Class of Stock [Axis] Pre-commencement Tender Offer Pre-commencement Tender Offer Entity Central Index Key Entity Central Index Key Entity Emerging Growth Company Entity Emerging Growth Company