| Condensed Consolidated Statements of Stockholders' Equity (Unaudited) (Parenthetical) - $ / shares | 3 Months Ended | ||||
|---|---|---|---|---|---|
| Nov. 05, 2020 | Dec. 31, 2020 | Sep. 30, 2020 | Dec. 31, 2019 | Sep. 30, 2019 | |
| Statement of Stockholders' Equity [Abstract] | |||||
| Cash dividends declared (in dollars per share) | $ 0.90 | $ 0.90 | $ 0.90 | $ 0.85 | $ 0.75 | 
| X | ||||||||||
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- Definition Aggregate dividends declared during the period for each share of common stock outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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| X | ||||||||||
| 
- References No definition available. 
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