Income taxes	6 Months Ended
Jul. 31, 2017
Income Tax Disclosure [Abstract]
Income taxes [Text Block]	Income taxes. The determination of the consolidated provision for income taxes, deferred tax assets and liabilities and related valuation allowances requires management to make judgments and estimates. As a company with subsidiaries in foreign jurisdictions, the process of calculating income taxes involves estimating current tax obligations and exposures in each jurisdiction as well as making judgments regarding the future recoverability of deferred tax assets. Income earned in the United Arab Emirates ("U.A.E.") is not subject to local country income tax. Additionally, the relative proportion of taxable income earned domestically versus internationally can fluctuate significantly from period to period. Changes in the estimated level of annual pre-tax income, tax laws and the results of tax audits can affect the overall effective income tax rate, which impacts the level of income tax expense and net income. Judgments and estimates related to the Company's projections and assumptions are inherently uncertain; therefore, actual results could differ materially from projections. The Company's effective tax rate ("ETR") from continuing operations for the second quarter and year-to-date was 24.9% and 16.8%, respectively, compared to 47.1% and 15.3% during the respective prior-year periods. The change in the ETR from the prior year-to-date to the current year-to-date was mainly due to changes in the foreign income and loss activities. The amount of unrecognized tax benefits, including interest and penalties, at July 31, 2017, recorded in other long-term liabilities was $0.2 million, all of which would impact the Company’s ETR if recognized. The Company includes accrued interest and penalties related to uncertain tax positions in income tax expense, with $1,200 included in expense for the current quarter. The amount of accrued interest and penalties at July 31, 2017 associated with unrecognized tax benefits was $47,900. The Company files income tax returns in U.S. federal and state jurisdictions. The Internal Revenue Service ("IRS") began an audit of the fiscal year ended January 31, 2015 in August 2016. In August 2017, the Company received a notice from the IRS that it had concluded the tax audit for the year ended January 31, 2015. No changes were made to the reported tax.

Income taxes. The determination of the consolidated provision for income taxes, deferred tax assets and liabilities and related valuation allowances requires management to make judgments and estimates. As a company with subsidiaries in foreign jurisdictions, the process of calculating income taxes involves estimating current tax obligations and exposures in each jurisdiction as well as making judgments regarding the future recoverability of deferred tax assets. Income earned in the United Arab Emirates ("U.A.E.") is not subject to local country income tax. Additionally, the relative proportion of taxable income earned domestically versus internationally can fluctuate significantly from period to period. Changes in the estimated level of annual pre-tax income, tax laws and the results of tax audits can affect the overall effective income tax rate, which impacts the level of income tax expense and net income. Judgments and estimates related to the Company's projections and assumptions are inherently uncertain; therefore, actual results could differ materially from projections.

The Company's effective tax rate ("ETR") from continuing operations for the second quarter and year-to-date was 24.9% and 16.8%, respectively, compared to 47.1% and 15.3% during the respective prior-year periods. The change in the ETR from the prior year-to-date to the current year-to-date was mainly due to changes in the foreign income and loss activities.

The amount of unrecognized tax benefits, including interest and penalties, at July 31, 2017, recorded in other long-term liabilities was $0.2 million, all of which would impact the Company’s ETR if recognized. The Company includes accrued interest and penalties related to uncertain tax positions in income tax expense, with $1,200 included in expense for the current quarter. The amount of accrued interest and penalties at July 31, 2017 associated with unrecognized tax benefits was $47,900.

The Company files income tax returns in U.S. federal and state jurisdictions. The Internal Revenue Service ("IRS") began an audit of the fiscal year ended January 31, 2015 in August 2016. In August 2017, the Company received a notice from the IRS that it had concluded the tax audit for the year ended January 31, 2015. No changes were made to the reported tax.