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

Annual report pursuant to Section 13 and 15(d)

INCOME TAXES - Narrative (Details)

INCOME TAXES - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended								6 Months Ended			9 Months Ended		12 Months Ended
INCOME TAXES - Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Mar. 31, 2017	Mar. 31, 2016
Income Tax Examination [Line Items]
Federal tax rate														21.00%	31.50%		35.00%
Income tax expense	$ 1,637	$ 337	$ 977	$ (575)	$ 48	$ (2,127)	$ 228	$ (1,262)	$ 402	$ (1,034)	$ (1,034)	$ 739	$ (3,161)	$ 2,376	$ (3,113)			$ 1,656
Federal operating loss	11,100													11,100
Acquired of operating loss	8,300													$ 8,300
Percentage of taxable income														80.00%
Unremitted foreign earnings	90,500													$ 90,500
Foreign withholding taxes														3,200
Penalties and interest expense in income tax examination														34,500
Unrecognized tax benefits	116,032				150,599									116,032	$ 150,599		$ 170,730	170,730	$ 171,374
Tax benefits that would impact tax rate	98,700													98,700
Income tax examonation penalties and interest accrued	900													$ 900
Income tax examination, likelihood of unfavorable settlement														We file our tax returns as prescribed by the laws of the jurisdictions in which we operate. Our U.S. tax returns have been audited for years through 2002 by the Internal Revenue Service. In other major jurisdictions, we are generally open to examination for the most recent three to five fiscal years. Although timing of the resolution and closure on audits is highly uncertain, we do not believe it is likely that the unrecognized tax benefits would materially change in the next 12 months.
2017 Tax Act [Member]
Income Tax Examination [Line Items]
Federal tax rate															31.50%
Increase decrease in income tax expense benefit															$ 50,600
Increase decrease in deferred tax assets															50,600
Repatriation of foreign earnings																$ 17,300
Undistributed earnings of foreign subsidiaries																8,800
Undistributed earnings of foreign subsidiaries net of inclusions						$ 8,500							$ 8,500			$ 8,500
Effective income tax interest deductions percent														30.00%
Effective income tax interest deductions amount														$ 28,500
Operating loss carryforwards subject to expiration	2,700													2,700
Other Noncurrent Liabilities [Member]
Income Tax Examination [Line Items]
Unrecognized tax benefits	5,600													5,600
Deferred Tax Asset [Member]
Income Tax Examination [Line Items]
Unrecognized tax benefits	111,400													111,400
Domestic Tax Authority
Income Tax Examination [Line Items]
Federal operating loss	332,100													332,100
Acquired of operating loss	$ 77,700													$ 77,700
Foreign Tax Authority
Income Tax Examination [Line Items]
Federal operating loss																	18,100	18,100
Acquired of operating loss																	$ 900	$ 900
Foreign Tax Authority \| Global Intangible Low Taxed Income [Member]
Income Tax Examination [Line Items]
Income tax credits														100.00%
Income tax expense														$ 500
State and Local Jurisdiction [Member]
Income Tax Examination [Line Items]
Federal operating loss					210,000										210,000
Acquired of operating loss					$ 40,000										$ 40,000