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Consolidated Statements of Equity (Parentheticals) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Retained Earnings [Member]
Cash dividends, amount per share (in dollars per share)	$ 0.59	$ 0.55
Cash dividends, amount per share (in dollars per share)	$ 0.59	$ 0.55
Cash dividends, amount per share (in dollars per share)			$ 2.51
Special dividends, amount per share (in dollars per share)			2.00
Cash dividends, amount per share (in dollars per share)			$ 2.51

X

- Definition

Aggregate special dividends declared during the period for each share of common stock outstanding.

+ References

No definition available.

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X

- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

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