Consolidated Statement of Changes in Shareholders' Equity (Parenthetical) - $ / shares	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Treasury Stock [Member] \| Series A Warrants [Member]
Exercise of warrants into shares of common stock			257,630
Exercise of warrants into shares of common stock			136,676
Retained Earnings [Member]
Common stock per share dividend amount	$ 4.40	$ 4.10	$ 3.55

Number of shares issued during the period as a result of the conversion of convertible securities.

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