Stockholders' Equity (Table Text Block)	12 Months Ended
Mar. 31, 2020
Stockholders' Equity Note [Abstract]
Common Stock Dividends	Common Stock Dividends Declared Date Per Share Amount Record Date Dividend Date December 4, 2019 $ 0.50 December 19, 2019 January 6, 2020 August 22, 2019 0.50 September 9, 2019 September 23, 2019 March 6, 2019 0.50 March 21, 2019 April 4, 2019 December 5, 2018 0.50 December 20, 2018 January 7, 2019 August 23, 2018 0.50 September 10, 2018 September 24, 2018 June 6, 2018 0.50 June 21, 2018 July 5, 2018

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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