Subsequent Events	6 Months Ended
Jun. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	16. Subsequent Event On July 7, 2021, we commenced offers to exchange our 7.00% capital securities due 2066 and 6.05% capital securities due 2067 for newly issued subordinated notes with the same respective maturities, and we are also soliciting consents to amend the indentures governing the capital securities to eliminate various terms and conditions and other provisions. The exchange offers and consent solicitations are being made pursuant to the terms and conditions set forth in the our preliminary prospectus included in our registration statement on Form S-4 relating to the issuance of the subordinated notes, which was filed with the SEC on July 7, 2021, but has not yet been declared effective.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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