CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Stockholders' Equity [Abstract]
Cash dividends declared (in dollars per share)	$ 0.26	$ 0.26	$ 0.78	$ 0.78
Distribution of shares of treasury stock for directors' compensation (in shares)			8,465	6,015
Distribution of shares of treasury stock for employee stock compensation (in shares)			2,373	1,784
Distribution of shares of treasury stock for directors deferred compensation shares (in shares)			2,551	36,681
Distribution of shares of treasury stock grants for employee restricted stock awards (in shares)			439
Sale of shares of treasury stock (in shares)	4,100	2,648	10,250	9,938
Purchase of shares of treasury stock (in shares)			272