Note 18 - Condensed Consolidating Cash Flow Information (Details) - USD ($) $ in Thousands	9 Months Ended
Feb. 29, 2016	Feb. 28, 2015
Parent Company [Member]
Net cash provided by (used in) operating activities	$ 10,666	$ 304
Net cash provided by (used in) investing activities	(8,860)	(10,188)
Net cash provided by (used in) financing activities	(6,475)	8,025
Effect of exchange rate changes on cash and cash equivalents	269	(1,338)
Increase (Decrease) in cash and cash equivalents	(4,400)	(3,197)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	7,080	4,863
CASH AND CASH EQUIVALENTS AT END OF PERIOD	2,680	1,666
Guarantor Subsidiaries [Member]
Net cash provided by (used in) operating activities	1,423	1,486
Net cash provided by (used in) investing activities	(1,671)	(1,582)
Net cash provided by (used in) financing activities	$ (7)	$ (18)
Effect of exchange rate changes on cash and cash equivalents
Increase (Decrease) in cash and cash equivalents	$ (255)	$ (114)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	(263)	(409)
CASH AND CASH EQUIVALENTS AT END OF PERIOD	(518)	(523)
Non-Guarantor Subsidiaries [Member]
Net cash provided by (used in) operating activities	(1,600)	1,447
Net cash provided by (used in) investing activities	3,890	(7,445)
Net cash provided by (used in) financing activities	(3,517)	(324)
Effect of exchange rate changes on cash and cash equivalents	(291)	(2,497)
Increase (Decrease) in cash and cash equivalents	(1,518)	(8,819)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	11,546	19,167
CASH AND CASH EQUIVALENTS AT END OF PERIOD	10,028	10,348
Consolidation, Eliminations [Member]
Net cash provided by (used in) operating activities	(3,648)	$ (445)
Net cash provided by (used in) investing activities	(6,009)
Net cash provided by (used in) financing activities	9,517	$ 324
Effect of exchange rate changes on cash and cash equivalents	$ 140	$ 121
Increase (Decrease) in cash and cash equivalents
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD
CASH AND CASH EQUIVALENTS AT END OF PERIOD
Net cash provided by (used in) operating activities	$ 6,841	$ 2,792
Net cash provided by (used in) investing activities	(12,650)	(19,215)
Net cash provided by (used in) financing activities	(482)	8,007
Effect of exchange rate changes on cash and cash equivalents	118	(3,714)
Increase (Decrease) in cash and cash equivalents	(6,173)	(12,130)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	18,363	23,621
CASH AND CASH EQUIVALENTS AT END OF PERIOD	$ 12,190	$ 11,491

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
-Paragraph 1
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6507016

Reference 5: http://www.xbrl.org/2003/role/presentationRef
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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of increase (decrease) from the effect of exchange rate changes on cash and cash equivalent balances held in foreign currencies.

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Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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