Income Taxes	9 Months Ended
Jan. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes An income tax benefit of $350,000 and an income tax expense of $20,000 was recorded for the three months ended January 31, 2020 and 2019, respectively. Income tax expense of $1,822,000 and $803,000 was recorded for the nine months ended January 31, 2020 and 2019, respectively. The effective tax rates were 15.5% and 57.1% for the three months ended January 31, 2020 and 2019, respectively. The effective tax rates were 104.5% and 21.8% for the nine months ended January 31, 2020 and 2019, respectively. The decrease in the effective tax rate for the three-month period is primarily due to the reduced federal tax liability which was a result of lower foreign subsidiary income inclusions and the recognition of the impact of the Company's assertion regarding the reinvestment of foreign unremitted earnings in the second quarter. The increase for the nine-month period is primarily due to the change in the Company’s assertion regarding the reinvestment of foreign unremitted earnings, the impact of foreign earnings, which are taxed at different tax rates than the US tax rate of 21%, and additional Global Intangible Low-Taxed Income ("GILTI") inclusion in the US. Effective August 1, 2019, the Company elected to amend the indefinite reinvestment of foreign unremitted earnings position set forth by ASC 740-30-25-17 and dissolve the indefinite reinvestment of unremitted earnings assertion for the Singapore, China, and Kewaunee Labway India Pvt. Ltd. international subsidiaries. The Company recorded a Dividend Distribution Tax withholding expense, imposed by the India Income Tax Department at a rate of 20.6%, in the amounts of $50,000 and $2,214,000 for the three and nine months ended January 31, 2020, respectively, related to the unremitted earnings of the subsidiaries paid to the parent company. The Company continues to include a deferred tax liability of $1,103,000 for unremitted earnings of the international subsidiaries as of January 31, 2020. The Company recorded all deferred tax assets and liabilities related to its outside basis differences in its foreign subsidiaries consistent with ASC 740.

Income Taxes

An income tax benefit of $350,000 and an income tax expense of $20,000 was recorded for the three months ended January 31, 2020 and 2019, respectively. Income tax expense of $1,822,000 and $803,000 was recorded for the nine months ended January 31, 2020 and 2019, respectively. The effective tax rates were 15.5% and 57.1% for the three months ended January 31, 2020 and 2019, respectively. The effective tax rates were 104.5% and 21.8% for the nine months ended January 31, 2020 and 2019, respectively. The decrease in the effective tax rate for the three-month period is primarily due to the reduced federal tax liability which was a result of lower foreign subsidiary income inclusions and the recognition of the impact of the Company's assertion regarding the reinvestment of foreign unremitted earnings in the second quarter. The increase for the nine-month period is primarily due to the change in the Company’s assertion regarding the reinvestment of foreign unremitted earnings, the impact of foreign earnings, which are taxed at different tax rates than the US tax rate of 21%, and additional Global Intangible Low-Taxed Income ("GILTI") inclusion in the US.

Effective August 1, 2019, the Company elected to amend the indefinite reinvestment of foreign unremitted earnings position set forth by ASC 740-30-25-17 and dissolve the indefinite reinvestment of unremitted earnings assertion for the Singapore, China, and Kewaunee Labway India Pvt. Ltd. international subsidiaries.

The Company recorded a Dividend Distribution Tax withholding expense, imposed by the India Income Tax Department at a rate of 20.6%, in the amounts of $50,000 and $2,214,000 for the three and nine months ended January 31, 2020, respectively, related to the unremitted earnings of the subsidiaries paid to the parent company. The Company continues to include a deferred tax liability of $1,103,000 for unremitted earnings of the international subsidiaries as of January 31, 2020. The Company recorded all deferred tax assets and liabilities related to its outside basis differences in its foreign subsidiaries consistent with ASC 740.