SEGMENT REPORTING (Summary of the Company's Segment Net Sales, Gross Profit and Segment Margin) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Segment reporting [Line Items]
Net Sales by Segment	$ 129,420us-gaap_SalesRevenueNet	$ 164,439us-gaap_SalesRevenueNet	$ 186,728us-gaap_SalesRevenueNet
Net Sales by Segment (as a percent)	100.00%utsi_SalesRevenueNetPercentage	100.00%utsi_SalesRevenueNetPercentage	100.00%utsi_SalesRevenueNetPercentage
Gross profit/(loss) by Segment	22,128us-gaap_GrossProfit	40,220us-gaap_GrossProfit	68,158us-gaap_GrossProfit
Gross profit/(loss) by Segment (as a percent)	17.00%utsi_GrossProfitPercentage	24.00%utsi_GrossProfitPercentage	37.00%utsi_GrossProfitPercentage
Segment Margin	7,666utsi_SegmentMargin	20,898utsi_SegmentMargin	30,765utsi_SegmentMargin
General and Corporate	(21,739)utsi_GeneralAndCorporateExpense	(34,131)utsi_GeneralAndCorporateExpense	(60,308)utsi_GeneralAndCorporateExpense
Operating loss	(14,073)us-gaap_OperatingIncomeLoss	(13,233)us-gaap_OperatingIncomeLoss	(29,543)us-gaap_OperatingIncomeLoss
Equipment [Member]
Segment reporting [Line Items]
Net Sales by Segment	105,988	141,138	160,688
Net Sales by Segment (as a percent)	82.00%	86.00%	86.00%
Gross profit/(loss) by Segment	21,000	41,250	64,835
Gross profit/(loss) by Segment (as a percent)	20.00%	29.00%	40.00%
Segment Margin	6,583	24,047	34,661
Equipment Based Services [Member]
Segment reporting [Line Items]
Net Sales by Segment	23,432	23,301	25,784
Net Sales by Segment (as a percent)	18.00%	14.00%	14.00%
Gross profit/(loss) by Segment	1,128	(1,030)	3,546
Gross profit/(loss) by Segment (as a percent)	5.00%	(4.00%)	14.00%
Segment Margin	1,105	(1,037)	3,524
Operational Support Services [Member]
Segment reporting [Line Items]
Net Sales by Segment			256
Net Sales by Segment (as a percent)	0.00%	0.00%	0.00%
Gross profit/(loss) by Segment			(223)
Gross profit/(loss) by Segment (as a percent)	0.00%	0.00%	(87.00%)
Segment Margin	$ (22)	$ (2,112)	$ (7,420)

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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Balance Type:	credit
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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

+ Details

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- Details

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- Definition

The aggregate total of general and corporate expenses.

+ References

No definition available.

+ Details

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- Definition

Represents the gross profit, expressed as a percentage of net sales revenue.

+ References

No definition available.

+ Details

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- Definition

Represents the net sales, expressed as a percentage of net sales revenue.

+ References

No definition available.

+ Details

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- Definition

Segment margin from sale of goods and services rendered during the reporting period, in the normal course of business.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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