Consolidated Statement of Changes in Shareholders' Equity (Parenthetical) - $ / shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Treasury Stock [Member] \| Series A Warrants [Member]
Exercise of warrants into shares of common stock		257,630	374,786
Exercise of warrants into shares of common stock		136,676	204,133
Retained Earnings [Member]
Common stock per share dividend amount	$ 4.10	$ 3.55	$ 3.00

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

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