Debt	9 Months Ended
Oct. 31, 2012
Debt [Abstract]
Debt Disclosure [Text Block]	Debt. On July 11, 2002, the Company entered into a secured loan and security agreement with a financial institution ("Loan Agreement"). Under the terms of the Loan Agreement as amended, which matures on November 30, 2013, the Company can borrow up to $38 million, subject to borrowing base and other requirements, under a revolving line of credit. The Loan Agreement covenants restrict debt, liens, investments, do not permit payment of dividends and require attainment of levels of profitability and cash flows. At October 31, 2012, the Company was in compliance with all covenants under the Loan Agreement. Interest rates are based on options selected by the Company as follows: (a) a margin in effect plus a prime rate; or (b) a margin in effect plus the LIBOR rate for the corresponding interest period. At October 31, 2012, the prime rate was 3.25% and the margins added to the prime rate and the LIBOR rate, which are determined each quarter based on the applicable financial statement ratio, were 0.50 and 2.75 percentage points, respectively. Monthly interest payments were made during the nine months ended October 31, 2012 and 2011. As of October 31, 2012, the Company had borrowed $17.8 million and had $8.7 million available to it under the revolving line of credit. In addition, $0.3 million of availability was used under the Loan Agreement primarily to support letters of credit to guarantee amounts committed for inventory purchases. The Loan Agreement provides that all domestic receipts are deposited in a bank account from which all funds may only be used to pay the debt under the Loan Agreement. At October 31, 2012, the amount of such restricted cash was $0.9 million. Cash required for operations is provided by draw downs on the line of credit. On April 10, 2012, the Company obtained a loan from a U.A.E. bank to purchase equipment and office furniture for a building for the piping system's facility in Saudi Arabia, in the amount of 22.2 million Dirhams, approximately $5.9 million U.S. dollars at the exchange rate prevailing on the transaction date. The loan bears interest at 5.5% with monthly payments of $97 thousand for both principal and interest and matures April 2017. On June 19, 2012, Perma-Pipe, Inc. borrowed $1.8 million under a mortgage note secured by its manufacturing facility in Lebanon, Tennessee. The proceeds were used for payment of amounts borrowed. The loan bears interest at 4.5% with monthly payments of $13 thousand for both principal and interest and matures July 1, 2027. On June 19, 2022, and on the same day of each year thereafter, the interest rate shall adjust to the prime rate provided the applicable interest rate shall not adjust more than 2% per annum, and shall be subject to ceiling of 18% and a floor of 4.5%.

Debt. On July 11, 2002, the Company entered into a secured loan and security agreement with a financial institution ("Loan Agreement"). Under the terms of the Loan Agreement as amended, which matures on November 30, 2013, the Company can borrow up to $38 million, subject to borrowing base and other requirements, under a revolving line of credit. The Loan Agreement covenants restrict debt, liens, investments, do not permit payment of dividends and require attainment of levels of profitability and cash flows. At October 31, 2012, the Company was in compliance with all covenants under the Loan Agreement. Interest rates are based on options selected by the Company as follows: (a) a margin in effect plus a prime rate; or (b) a margin in effect plus the LIBOR rate for the corresponding interest period. At October 31, 2012, the prime rate was 3.25% and the margins added to the prime rate and the LIBOR rate, which are determined each quarter based on the applicable financial statement ratio, were 0.50 and 2.75 percentage points, respectively. Monthly interest payments were made during the nine months ended October 31, 2012 and 2011. As of October 31, 2012, the Company had borrowed $17.8 million and had $8.7 million available to it under the revolving line of credit. In addition, $0.3 million of availability was used under the Loan Agreement primarily to support letters of credit to guarantee amounts committed for inventory purchases. The Loan Agreement provides that all domestic receipts are deposited in a bank account from which all funds may only be used to pay the debt under the Loan Agreement. At October 31, 2012, the amount of such restricted cash was $0.9 million. Cash required for operations is provided by draw downs on the line of credit.

On April 10, 2012, the Company obtained a loan from a U.A.E. bank to purchase equipment and office furniture for a building for the piping system's facility in Saudi Arabia, in the amount of 22.2 million Dirhams, approximately $5.9 million U.S. dollars at the exchange rate prevailing on the transaction date. The loan bears interest at 5.5% with monthly payments of $97 thousand for both principal and interest and matures April 2017.

On June 19, 2012, Perma-Pipe, Inc. borrowed $1.8 million under a mortgage note secured by its manufacturing facility in Lebanon, Tennessee. The proceeds were used for payment of amounts borrowed. The loan bears interest at 4.5% with monthly payments of $13 thousand for both principal and interest and matures July 1, 2027. On June 19, 2022, and on the same day of each year thereafter, the interest rate shall adjust to the prime rate provided the applicable interest rate shall not adjust more than 2% per annum, and shall be subject to ceiling of 18% and a floor of 4.5%.