Consolidated Statement of Changes in Shareholders' Equity (Unaudited) (Parenthetical) - $ / shares shares in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Retained Earnings [Member]
Common stock per share dividend amount	$ 1.00	$ 1.00	$ 3.00	$ 2.55
Treasury Stock [Member] \| Series A Warrants [Member]
Exercise of warrants into shares of common stock		22,291		76,517
Exercise of warrants into shares of common stock		12,758		45,426

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

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration