Quantum Corporation Annual report pursuant to Section 13 and 15(d)

GEOGRAPHIC INFORMATION - Schedule of Revenue and Long-Lived Assets by Region (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Long- Lived Assets	$ 11,186				$ 12,939				$ 11,186	$ 12,939	$ 14,653
Revenue	120,835	$ 133,484	$ 134,742	$ 116,284	120,029	$ 128,048	$ 117,025	$ 110,856	505,345	475,958	553,095
Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Long- Lived Assets	10,914				12,657				10,914	12,657	14,063
Revenue									324,839	304,007	340,811
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Long- Lived Assets	170				145				170	145	421
Revenue									127,890	124,821	152,186
Asia Pacific
Revenues from External Customers and Long-Lived Assets [Line Items]
Long- Lived Assets	$ 102				$ 137				102	137	169
Revenue									$ 52,616	$ 47,130	$ 60,098