CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	12 Months Ended
Jan. 31, 2012	Jan. 31, 2011	Jan. 31, 2010
Cash flows from operating activities
Net income	$ 7,133,701	$ 6,139,132	$ 4,439,811
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	1,914,418	1,824,685	1,931,512
Deferred income taxes	1,197,654	439,069	406,754
(Gain) loss on sales of property and equipment, net	102,386	8,231	(20,585)
Stock-based compensation	744,306	645,891	645,967
Allowance for doubtful accounts	46,986	240,133	37,189
Changes in operating assets and liabilities:
Accounts receivable	(2,173,195)	(1,464,863)	6,409,090
Inventories	(2,450,559)	676,071	4,280,330
Prepaid expenses, deposits and other assets	(350,416)	(243,598)	(9,904)
Accounts payable and accrued expenses	3,116,045	977,454	(2,551,921)
Customers' advances	2,323,603	22,004	524,678
Accrued pension retirement benefits	(2,647,339)	(668,901)	(449,405)
Other non-current liabilities	2,197	2,197	2,197
Net cash provided by operating activities	8,959,787	8,597,505	15,645,713
Cash flows from investing activities
Proceeds from sale of property and equipment	33,566	36,387	40,318
Acquisitions of property and equipment	(2,097,233)	(1,665,949)	(2,133,807)
Purchase of investments	(1,010,535)	(745,218)	(1,445,004)
Proceeds from maturities of investments	497,155	725,004	720,000
Payment for acquisition of business	0	(955,268)	0
Net cash used in investing activities	(2,577,047)	(2,605,044)	(2,818,493)
Cash flows from financing activities
Proceeds from new borrowing	477,692	189,074	485,336
Reduction of debt	(727,399)	(717,134)	(926,497)
Exercise of stock options	152,970	780,834	225,584
Payment of dividends	(3,943,332)	(3,597,539)	(3,504,026)
Purchase of treasury shares	(167,534)	(935,631)	(251,612)
Net cash used in financing activities	(4,207,603)	(4,280,396)	(3,971,215)
Effect of exchange rate changes on cash	5,443	26,645	56,446
Net increase in cash and cash equivalents	2,180,580	1,738,710	8,912,451
Cash and cash equivalents at beginning of year	32,400,814	30,662,104	21,749,653
Cash and cash equivalents at end of year	$ 34,581,394	$ 32,400,814	$ 30,662,104

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).