Computation of Net Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands |
3 Months Ended | 9 Months Ended | |
|---|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
Dec. 31, 2017 |
|
| Computation of net earnings per share | |||
| Net earnings | $ 20,083 | $ 10,510 | $ 34,214 |
| Average basic shares outstanding (shares) | 10,915 | 10,998 | |
| Basic net earnings per share (usd per share) | $ 1.84 | $ 0.96 | |
| Average diluted shares outstanding (shares) | 11,009 | 11,127 | |
| Diluted net earnings per share (usd per share) | $ 1.82 | $ 0.94 | |
| Restricted stock not vested | |||
| Computation of net earnings per share | |||
| Dilutive shares (shares) | 8 | 33 | |
| Dilutive effect of Performance Share Plan | |||
| Computation of net earnings per share | |||
| Dilutive shares (shares) | 86 | 96 | |