Shares And Stockholders' Equity (Preferred Stock Per Share And Aggregate Dividends) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Dividend Per Share	$ 1,718.75		$ 3,535.94
Dividends, Preferred Stock	$ 34		$ 71
Series C Preferred Stock [Member]
Dividend Per Share	$ 1,156.25		$ 1,792.19
Dividends, Preferred Stock	$ 23		$ 36
Series D Preferred Stock [Member]
Dividend Per Share	$ 562.50		$ 1,743.75
Dividends, Preferred Stock	$ 11		$ 35

Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-SubTopic 405
-Topic 942
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481071/942-405-45-2

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Period Type:	duration