Note 11 - Segment Information - Financial Information Relating to Geographic Areas (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015
External sales	$ 156,578	$ 144,037	$ 131,807	$ 130,581	$ 134,762	$ 130,973	$ 120,907	$ 112,381	$ 563,003	$ 499,023	$ 452,246
Long-lived assets	135,124				132,362				135,124	132,362	129,749
UNITED STATES
External sales									313,195	275,859	245,217
EMEA, excluding U.K. [Member]
External sales									125,126	103,060	104,178
UNITED KINGDOM
External sales									28,401	28,307	32,309
APAC, excluding Greater China [Member]
External sales									41,463	38,137	24,015
CHINA
External sales									39,078	36,199	34,933
Long-lived assets	1,165				1,109				1,165	1,109	1,286
Rest of World [Member]
External sales									15,740	17,461	11,594
United States and Canada [Member]
Long-lived assets	119,859				116,830				119,859	116,830	117,224
Europe [Member]
Long-lived assets	$ 14,100				$ 14,423				$ 14,100	$ 14,423	$ 11,239