Quantum Corporation Quarterly report pursuant to Section 13 or 15(d)

FAIR VALUE - Schedule of Carrying Value and Fair Value of Financial Liabilities (Details)

FAIR VALUE - Schedule of Carrying Value and Fair Value of Financial Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Mar. 31, 2016
Carrying Value
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Total long-term debt	$ 72,239	$ 65,709
Level 2 fair value measurements \| Fair Value
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Total long-term debt	75,999	65,741
Convertible subordinated debt \| Carrying Value
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Total long-term debt	64,219	69,253
Convertible subordinated debt \| Level 2 fair value measurements \| Fair Value
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Total long-term debt	61,999	51,686
Credit agreement \| Carrying Value \| Credit agreement with Wells Fargo
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Total long-term debt	0	65,709
Credit agreement \| Carrying Value \| Revolving credit agreement \| Revolving credit agreement
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Total long-term debt	24,219	0
Credit agreement \| Level 2 fair value measurements \| Fair Value \| Credit agreement with Wells Fargo
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Total long-term debt	0	65,741
Credit agreement \| Level 2 fair value measurements \| Fair Value \| Revolving credit agreement \| Revolving credit agreement
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Total long-term debt	25,998	0
Term loan agreement \| Carrying Value
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Total long-term debt	48,020	0
Term loan agreement \| Level 2 fair value measurements \| Fair Value
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Total long-term debt	$ 50,001	$ 0