| Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] |
| | | | | (in thousands, except share and per share amounts) | | Three Months Ended July 31, 2019 | | | December 6, 2018
through
July 31,
2019 | | | Net income (loss) attributable to Concrete Pumping Holdings, Inc. | | $ | 2,762 | | | $ | (10,513 | ) | | Less: Undistributed earnings allocated to participating securities | | | (53 | ) | | | - | | | Less: Preferred stock - cumulative dividends | | | (456 | ) | | | (1,159 | ) | | Net income (loss) attributable to common stockholders (numerator for basic earnings per share) | | $ | 2,253 | | | $ | (11,672 | ) | | Add back: Undistributed earnings allocated to participating securities | | | 53 | | | | - | | | Less: Undistributed earnings reallocated to participating securities | | | (51 | ) | | | - | | | Add back: Preferred stock - cumulative dividends | | | 456 | | | | - | | | Numerator for diluted earnings per share | | $ | 2,711 | | | $ | (11,672 | ) | | | | | | | | | | | | Weighted average shares (denominator): | | | | | | | | | | Weighted average shares - basic | | | 49,940,411 | | | | 37,155,182 | | | Weighted average shares - diluted | | | 53,122,690 | | | | 37,155,182 | | | | | | | | | | | | | Basic earnings (loss) per share | | $ | 0.05 | | | $ | (0.31 | ) | | Diluted earnings (loss) per share | | $ | 0.05 | | | $ | (0.31 | ) | | | | | | | | | November 1, 2018
through
December 5,
2018 | | | | | | | | | Net (loss) income attributable to Concrete Pumping Holdings, Inc | | $ | (22,575 | ) | | $ | 4,825 | | | $ | 26,993 | | | Less: Preferred stock - cumulative dividends | | | (126 | ) | | $ | (1,050 | ) | | | (1,050 | ) | | Less: Undistributed earnings allocated to preferred shares | | | - | | | $ | (892 | ) | | | (6,127 | ) | | Net (loss) income available to common shareholders | | $ | (22,701 | ) | | $ | 2,883 | | | $ | 19,816 | | | | | | | | | | | | | | | | | Weighted average shares (denominator): | | | | | | | | | | | | | | Weighted average shares - basic | | $ | 7,576,289 | | | $ | 7,576,289 | | | $ | 7,576,289 | | | Weighted average shares - diluted | | $ | 7,576,289 | | | $ | 8,510,779 | | | $ | 8,510,779 | | | | | | | | | | | | | | | | | Antidilutive stock options | | $ | 932,746 | | | | - | | | | - | | | | | | | | | | | | | | | | | Basic income (loss) per share | | $ | (3.00 | ) | | $ | 0.38 | | | $ | 2.62 | | | Diluted income (loss) per share | | $ | (3.00 | ) | | $ | 0.34 | | | $ | 2.33 | | |