Consolidated Statements of Stockholders' Equity (unaudited) (Parenthetical) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Consolidated Statements of Stockholders' Equity (unaudited) [Abstract]
Cash dividends - per share (in dollars per share)	$ 0.00	$ 0.00	$ 0.52	$ 0.48
Net issuance of shares to employee benefit plans and other stock plans (in shares)	29,525	31,546	96,445	104,390