The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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No definition available.

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

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Aggregate revenue recognized during the period (derived from goods sold, services rendered, insurance premiums, or other activities that constitute an entity's earning process). For financial services companies, also includes investment and interest income, and sales and trading gains.

+ 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=6880815&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

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Business Segments and Enterprise-Wide Disclosures (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2013 OperatingSegments	Mar. 31, 2012	Mar. 31, 2011
Segment Reporting Information [Line Items]
Number of operating segments									2
Sales to external customers	$ 28,515	$ 24,948	$ 22,491	$ 23,223	$ 24,600	$ 22,211	$ 21,852	$ 22,408	$ 99,177	$ 91,071	$ 97,088
Gross margin									45,546	42,946	42,235
Depreciation and amortization									4,951	4,351	3,432
Income (loss) from operations	(1,380)	(1,769)	(18,418)	(644)	(4,797)	(974)	(383)	246	(22,211)	(5,908)	(2,603)
AMI
Segment Reporting Information [Line Items]
Sales to external customers									54,110	41,415	34,584
Gross margin									32,767	26,646	23,314
Depreciation and amortization									4,153	3,737	2,989
Income (loss) from operations									(11,548)	728	2,004
HE
Segment Reporting Information [Line Items]
Sales to external customers									45,067	49,656	62,504
Gross margin									12,779	16,300	18,921
Depreciation and amortization									287	315	234
Income (loss) from operations									7,076	9,595	11,424
Other
Segment Reporting Information [Line Items]
Sales to external customers									0	0	0
Gross margin									0	0	0
Depreciation and amortization									511	299	209
Income (loss) from operations									$ (17,739)	$ (16,231)	$ (16,031)