Stockholders' Equity (Table Text Block)	12 Months Ended
Mar. 31, 2021
Stockholders' Equity Note [Abstract]
Common Stock Dividends	Common Stock Dividends Declared Date Per Share Amount Record Date Dividend Date December 9, 2020 $ 2.00 December 21, 2020 December 30, 2020 August 20, 2020 0.50 September 7, 2020 September 21, 2020 December 4, 2019 0.50 December 19, 2019 January 6, 2020 August 22, 2019 0.50 September 9, 2019 September 23, 2019

Tabular disclosure of changes in the separate accounts comprising stockholders' equity (in addition to retained earnings) and of the changes in the number of shares of equity securities during at least the most recent annual fiscal period and any subsequent interim period presented is required to make the financial statements sufficiently informative if both financial position and results of operations are presented.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

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Period Type:	duration