CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) shares in Thousands, $ in Thousands | Common Stock | Capital in Excess of Par Value | Retained Earnings | Accumulated Other Comprehensive Income (Loss) | Total |
Balance at Dec. 31, 2017 | $ 3,457 | | $ 68,127 | $ (1,980) | $ 69,604 |
Balance (in shares) at Dec. 31, 2017 | 34,572 | | | | |
Increase (Decrease) in Stockholders' Equity [Roll Forward] | | | | | |
Stock issued for stock incentive plans, net | $ 20 | $ 496 | | | 516 |
Stock issued for stock incentive plans, net (in shares) | 194 | | | | |
Stock purchased and retired | $ (20) | (496) | (2,419) | | (2,935) |
Stock purchased and retired (in shares) | (200) | | | | |
Net income | | | 7,609 | | 7,609 |
Pension adjustment, net of taxes | | | | 19 | 19 |
Unrealized gain on securities, net of taxes and reclassification adjustment | | | | 7 | 7 |
Dividends paid | | | (3,465) | | (3,465) |
Balance at Mar. 31, 2018 | $ 3,457 | | 69,852 | (1,954) | 71,355 |
Balance (in shares) at Mar. 31, 2018 | 34,566 | | | | |
Balance at Dec. 31, 2017 | $ 3,457 | | 68,127 | (1,980) | 69,604 |
Balance (in shares) at Dec. 31, 2017 | 34,572 | | | | |
Increase (Decrease) in Stockholders' Equity [Roll Forward] | | | | | |
Net income | | | | | 23,760 |
Pension adjustment, net of taxes | | | | | 51 |
Unrealized gain on securities, net of taxes and reclassification adjustment | | | | | 16 |
Balance at Sep. 30, 2018 | $ 3,450 | | 78,958 | (1,913) | 80,495 |
Balance (in shares) at Sep. 30, 2018 | 34,499 | | | | |
Balance at Mar. 31, 2018 | $ 3,457 | | 69,852 | (1,954) | 71,355 |
Balance (in shares) at Mar. 31, 2018 | 34,566 | | | | |
Increase (Decrease) in Stockholders' Equity [Roll Forward] | | | | | |
Stock issued for stock incentive plans, net | $ (1) | 529 | | | 528 |
Stock issued for stock incentive plans, net (in shares) | (1) | | | | |
Stock purchased and retired | $ (1) | (529) | 259 | | (271) |
Stock purchased and retired (in shares) | (17) | | | | |
Net income | | | 8,990 | | 8,990 |
Pension adjustment, net of taxes | | | | 15 | 15 |
Unrealized gain on securities, net of taxes and reclassification adjustment | | | | 9 | 9 |
Dividends paid | | | (3,455) | | (3,455) |
Balance at Jun. 30, 2018 | $ 3,455 | | 75,646 | (1,930) | 77,171 |
Balance (in shares) at Jun. 30, 2018 | 34,548 | | | | |
Increase (Decrease) in Stockholders' Equity [Roll Forward] | | | | | |
Stock issued for stock incentive plans, net | $ 0 | 528 | | | 528 |
Stock issued for stock incentive plans, net (in shares) | 0 | | | | |
Stock purchased and retired | $ (5) | (528) | (397) | | (930) |
Stock purchased and retired (in shares) | (49) | | | | |
Net income | | | 7,161 | | 7,161 |
Pension adjustment, net of taxes | | | | 17 | 17 |
Dividends paid | | | (3,452) | | (3,452) |
Balance at Sep. 30, 2018 | $ 3,450 | | 78,958 | (1,913) | 80,495 |
Balance (in shares) at Sep. 30, 2018 | 34,499 | | | | |
Balance at Dec. 31, 2018 | $ 3,433 | | 73,954 | (2,175) | 75,212 |
Balance (in shares) at Dec. 31, 2018 | 34,328 | | | | |
Increase (Decrease) in Stockholders' Equity [Roll Forward] | | | | | |
Stock issued for stock incentive plans, net | $ 14 | 524 | | | 538 |
Stock issued for stock incentive plans, net (in shares) | 141 | | | | |
Stock purchased and retired | $ (34) | (524) | (4,338) | | (4,896) |
Stock purchased and retired (in shares) | (344) | | | | |
Net income | | | 7,469 | | 7,469 |
Pension adjustment, net of taxes | | | | 17 | 17 |
Unrealized gain on securities, net of taxes and reclassification adjustment | | | | 7 | 7 |
Dividends paid | | | (4,117) | | (4,117) |
Balance at Mar. 31, 2019 | $ 3,413 | | 73,382 | (2,565) | 74,230 |
Balance (in shares) at Mar. 31, 2019 | 34,125 | | | | |
Balance at Dec. 31, 2018 | $ 3,433 | | 73,954 | (2,175) | 75,212 |
Balance (in shares) at Dec. 31, 2018 | 34,328 | | | | |
Increase (Decrease) in Stockholders' Equity [Roll Forward] | | | | | |
Net income | | | | | 24,697 |
Pension adjustment, net of taxes | | | | | 50 |
Unrealized gain on securities, net of taxes and reclassification adjustment | | | | | 7 |
Balance at Sep. 30, 2019 | $ 3,396 | | 81,273 | (2,532) | 82,137 |
Balance (in shares) at Sep. 30, 2019 | 33,960 | | | | |
Increase (Decrease) in Stockholders' Equity [Roll Forward] | | | | | |
Adoption of accounting standard (Note 2) | | | 414 | (414) | |
Balance at Mar. 31, 2019 | $ 3,413 | | 73,382 | (2,565) | 74,230 |
Balance (in shares) at Mar. 31, 2019 | 34,125 | | | | |
Increase (Decrease) in Stockholders' Equity [Roll Forward] | | | | | |
Stock issued for stock incentive plans, net | $ (1) | 545 | | | 544 |
Stock issued for stock incentive plans, net (in shares) | (11) | | | | |
Stock purchased and retired | $ (8) | (545) | (443) | | (996) |
Stock purchased and retired (in shares) | (69) | | | | |
Net income | | | 9,373 | | 9,373 |
Pension adjustment, net of taxes | | | | 17 | 17 |
Dividends paid | | | (4,092) | | (4,092) |
Balance at Jun. 30, 2019 | $ 3,404 | | 78,220 | (2,548) | 79,076 |
Balance (in shares) at Jun. 30, 2019 | 34,045 | | | | |
Increase (Decrease) in Stockholders' Equity [Roll Forward] | | | | | |
Stock issued for stock incentive plans, net | | 544 | | | 544 |
Stock purchased and retired | $ (8) | $ (544) | (719) | | (1,271) |
Stock purchased and retired (in shares) | (85) | | | | |
Net income | | | 7,855 | | 7,855 |
Pension adjustment, net of taxes | | | | 16 | 16 |
Dividends paid | | | (4,083) | | (4,083) |
Balance at Sep. 30, 2019 | $ 3,396 | | $ 81,273 | $ (2,532) | 82,137 |
Balance (in shares) at Sep. 30, 2019 | 33,960 | | | | |
Increase (Decrease) in Stockholders' Equity [Roll Forward] | | | | | |
Adoption of accounting standard (Note 2) | | | | | $ 414 |