Westell (WSTL) 10-Q 6 Feb 15 2015 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Dec. 31, 2014	Jan. 20, 2015
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Dec-14
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q3
Entity Registrant Name	WESTELL TECHNOLOGIES INC
Entity Central Index Key	1002135
Current Fiscal Year End Date	-28
Entity Filer Category	Accelerated Filer
Class A Common Stock
Entity Common Stock, Shares Outstanding		46,256,686
Class B Common Stock
Entity Common Stock, Shares Outstanding		13,937,151

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (Unaudited) (USD $)	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$17,699	$35,793
Short-term investments	25,222	15,584
Accounts receivable (net of allowance of $53 and $40 at December 31, 2014, and March 31, 2014, respectively)	7,132	15,831	[1]
Inventories	22,909	24,056	[1]
Prepaid expenses and other current assets	2,729	1,952	[1]
Deferred income taxes	875	899
Assets available-for-sale	1,044	1,044
Total current assets	77,610	95,159	[1]
Property and equipment, gross	19,420	17,902	[1]
Less accumulated depreciation and amortization	-16,486	-16,001
Property and equipment, net	2,934	1,901	[1]
Goodwill	0	31,102	[1]
Intangible assets, net	27,461	32,319	[1]
Other non-current assets	250	393
Total assets	108,255	160,874	[1]
Current liabilities:
Accounts payable	4,536	7,067	[1]
Accrued expenses	3,083	3,418
Accrued compensation	959	4,395
Contingent consideration	727	2,067
Deferred revenue	519	1,774
Total current liabilities	9,824	18,721	[1]
Deferred revenue non-current	772	787
Deferred income tax liability	1,045	1,072
Contingent consideration non-current	811	574
Other non-current liabilities	527	528
Total liabilities	12,979	21,682	[1]
Commitments and contingencies (Note 11)
Stockholders’ equity:
Preferred stock, par $0.01, Authorized - 1,000,000 shares. Issued and outstanding - none	0	0
Additional paid-in capital	411,953	410,176
Treasury stock at cost – 17,350,483 and 17,130,965 shares at December 31, 2014, and March 31, 2014, respectively	-34,897	-34,206
Cumulative translation adjustment	608	608
Accumulated deficit	-282,991	-237,984	[1]
Total stockholders’ equity	95,276	139,192	[1]
Total liabilities and stockholders’ equity	108,255	160,874	[1]
Class A Common Stock
Stockholders’ equity:
Common stock, value	464	459
Class B Common Stock
Stockholders’ equity:
Common stock, value	$139	$139
[1]	Certain amounts have been adjusted to reflect measurement period adjustments related to the CSI acquisition.

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $)	Dec. 31, 2014	Mar. 31, 2014
In Thousands, except Share data, unless otherwise specified
Accounts receivable, allowance	$53	$40
Preferred stock, par value	$0.01	$0.01
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Treasury stock, shares	17,350,483	17,130,965
Class A Common Stock
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	109,000,000	109,000,000
Common stock, shares outstanding	46,256,686	45,852,740
Class B Common Stock
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	25,000,000	25,000,000
Common stock, shares issued	13,937,151	13,937,151
Common stock, shares outstanding	13,937,151	13,937,151

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Operations (Unaudited) (USD $)	3 Months Ended				9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2014		Dec. 31, 2013
Income Statement [Abstract]
Revenue	$14,043		$25,236		$65,514		$77,652
Cost of revenue	9,648		13,304	[1]	43,370		45,281	[1]
Gross profit	4,395		11,932	[1]	22,144		32,371	[1]
Operating expenses:
Sales and marketing	2,719		3,205	[1]	9,064		9,749	[1]
Research and development	4,353		2,527		13,128		7,845
General and administrative	2,797		3,402		9,131		10,200
Intangible amortization	1,562		737		4,857		3,588
Restructuring	0		38		55		273
Goodwill impairment	20,547				31,102
Total operating expenses	31,978		9,909	[1]	67,337		31,655	[1]
Operating income (loss)	-27,583		2,023		-45,193		716
Other income (expense), net	-29		-31		16		-63
Income (loss) before income taxes and discontinued operations	-27,612		1,992		-45,177		653
Income tax benefit (expense)	72		-38		170		-125
Net income (loss) from continuing operations	-27,540		1,954		-45,007		528
Discontinued Operations:
Income (loss) from discontinued operations, net of tax benefit			-29				-39
Net income (loss) (2)	($27,540)	[2]	$1,925	[2]	($45,007)	[2]	$489	[2]
Basic net income (loss) per share:
Basic net income (loss) from continuing operations	($0.46)		$0.03		($0.75)		$0.01
Basic net loss from discontinued operations	$0		$0		$0		$0
Basic net income (loss) per share	($0.46)		$0.03		($0.75)		$0.01
Diluted net income (loss) per share:
Diluted net income (loss) from continuing operations	($0.46)		$0.03		($0.75)		$0.01
Diluted net loss from discontinued operations	$0		$0		$0		$0
Diluted net income (loss) per share	($0.46)		$0.03		($0.75)		$0.01
Weighted-average number of common shares outstanding:
Basic	60,016		58,834		59,885		58,678
Effect of dilutive securities: restricted stock, restricted stock units, performance stock units and stock options(3)	0	[3]	1,816	[3]	0	[3]	1,087	[3]
Diluted	60,016		60,650		59,885		59,765
[1]	Certain amounts have been reclassified to reflect a change in accounting principle. See Note 1.
[2]	Net income (loss) and comprehensive income (loss) are the same for the periods reported.
[3]	The Company had 43 thousand and 85 thousand shares represented by options for the three and nine months ended December 31, 2013, respectively, which were not included in the computation of average dilutive shares outstanding because there were anti-dilutive. In periods with a net loss, the basic loss per share equals the diluted loss per share as all common stock equivalents are excluded from the per share calculation.

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Operations Condensed Consolidated Statements of Operations Parenthetical (Unaudited)	3 Months Ended	9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2013
Income Statement [Abstract]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	43	85

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Cash flows from operating activities:
Net income (loss)	($45,007)	[1]	$489	[1]
Reconciliation of net loss to net cash used in operating activities:
Depreciation and amortization	5,599		4,037
Goodwill impairment	31,102
Stock-based compensation	1,628		1,293
Restructuring	55		273
Exchange rate loss	8		96
Changes in assets and liabilities:
Accounts receivable	8,699		-1,614
Inventories	1,147		-3,276
Prepaid expenses and other current assets	-780		585
Other assets	146		164
Deferred revenue	-1,270		-1,989
Accounts payable and accrued expenses	-2,622		-746
Accrued compensation	-3,436		1,379
Net cash provided by (used in) operating activities	-4,731		691
Cash flows from investing activities:
Maturities of held-to-maturity short-term debt securities	18,072		24,228
Maturities of other short-term investments	1,476		3,682
Purchases of held-to-maturity short-term debt securities	-20,773		-19,244
Purchases of other short-term investments	-8,413		-1,476
Purchases of property and equipment	-1,773		-399
Acquisitions, net of cash acquired	-304		-28,945
Changes in restricted cash			2,500
Net cash used in investing activities	-11,715		-19,654
Cash flows from financing activities:
Purchases of treasury stock	-692		-319
Proceeds from stock options exercised	155		718
Payment of contingent consideration	-1,104
Net cash provided by (used) in financing activities	-1,641		399
Loss of exchange rate changes on cash	-7		-20
Net decrease in cash and cash equivalents	-18,094		-18,584
Cash and cash equivalents, beginning of period	35,793		88,233
Cash and cash equivalents, end of period	$17,699		$69,649
[1]	Net income (loss) and comprehensive income (loss) are the same for the periods reported.

Basis_of_Presentation

Basis of Presentation	9 Months Ended
	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation
	Description of Business
	Westell Technologies, Inc. (the Company) is a holding company. Its wholly-owned subsidiary, Westell, Inc., designs and distributes telecommunications products which are sold primarily to major telephone companies. Noran Tel, Inc. is a wholly-owned subsidiary of Westell, Inc. Noran Tel's operations focus on power distribution product development and sales of Company products in Canada. On April 1, 2013, Westell, Inc. acquired 100% of the outstanding shares of Kentrox, Inc. (Kentrox). Kentrox designed and distributed intelligent site management solutions that provided comprehensive monitoring, management and control of any site. On March 1, 2014, Westell, Inc. acquired 100% of the outstanding shares of Cellular Specialties, Inc. (CSI). CSI designs and develops in-building wireless solutions including distributed antenna systems (DAS) products and small cell connectivity equipment. The assets and liabilities acquired and the results of operations relating to CSI are included in the Company's Condensed Consolidated Financial Statements from the date of acquisition.
	Basis of Presentation and Reporting
	The accompanying Condensed Consolidated Financial Statements include the accounts of the Company and its wholly-owned subsidiaries. The Condensed Consolidated Financial Statements have been prepared using generally accepted accounting principles (GAAP) in the United States for interim financial reporting, and consistent with the instructions of Form 10-Q and Article 10 of Regulation S-X, and accordingly they do not include all of the information and footnotes required in the annual consolidated financial statements and accompanying footnotes. The Condensed Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements and accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended March 31, 2014. All intercompany accounts and transactions have been eliminated in consolidation.
	In the opinion of management, the unaudited interim financial statements included herein reflect all adjustments, consisting of normal recurring adjustments, necessary to present fairly the Company’s condensed consolidated financial position and the results of operations, comprehensive income (loss) and cash flows at December 31, 2014, and for all periods presented. The results of operations for the periods presented are not necessarily indicative of the results that may be expected for fiscal year 2015.
	Use of Estimates
	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, and that affect revenue and expenses during the periods reported. Estimates are used when accounting for the allowance for uncollectible accounts receivable, net realizable value of inventory, product warranty accrued, relative selling prices, stock-based compensation, goodwill and intangible assets fair value, depreciation, income taxes, and contingencies, among other things. Actual results could differ from those estimates.
	Recently Issued Accounting Pronouncements
	In August 2014, the FASB issued ASU No. 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern (ASU 2014-15), to provide guidance on management’s responsibility in evaluating whether there is substantial doubt about a company’s ability to continue as a going concern and to provide related footnote disclosures. The amendments in this update are effective for the annual period ending after December 15, 2016, and for annual periods and interim periods thereafter. Early application is permitted. The Company does not expect the adoption of ASU 2014-15 to have a significant impact on its Consolidated Financial Statements or related disclosures.
	In May 2014, the FASB issued ASU No. 2014-09, Revenue From Contracts With Customers (ASU 2014-09), that outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. The ASU is based on the principle that an entity should recognize revenue to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The ASU also requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts, including significant judgments and changes in judgments and assets recognized from costs incurred to fulfill a contract. Entities have the option of using either a full retrospective or a modified retrospective approach for the adoption of the new standard. The ASU becomes effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period; early adoption is not permitted. The Company is currently assessing the impact that ASU 2014-09 will have on its Consolidated Financial Statements.
	Update to Significant Accounting Policies
	A complete description of the Company’s significant accounting policies is discussed in the Company’s Annual Report on Form 10-K for the fiscal year ended March 31, 2014. There have been no material changes in our critical accounting policies from those disclosed in our Annual Report on Form 10-K for the year ended March 31, 2014, except as set forth below.
	Voluntary Change in Accounting Principle
	Effective April 1, 2014, the Company made a voluntary change in accounting principle to classify shipping and handling costs associated with the distribution of finished product to our customers as cost of revenue (previously recorded in sales and marketing expense). The Company made the voluntary change in principle because it believes the classification of shipping and handling costs in cost of revenue better reflects the cost of producing and distributing products. It also enhances the comparability of the financial statements with many industry peers. As required by U.S. generally accepted accounting principles, the change has been reflected in the Condensed Consolidated Statements of Operations through retrospective application of the change in accounting principle.
	The following table provides the reconciliation from previously reported financial data as adjusted:
		Three months ended December 31, 2013									Nine months ended December 31, 2013
	(in thousands)	Previously reported			Effect of Accounting Principle Change			Adjusted			Previously reported			Effect of Accounting Principle Change			Adjusted
	Revenue	$	25,236		$	—		$	25,236		$	77,652		$	—		$	77,652
	Cost of revenue	13,001			303			13,304			44,218			1,063			45,281
	Gross profit	$	12,235		$	(303	)	$	11,932		$	33,434		$	(1,063	)	$	32,371
	Gross margin	48.5		%				47.3		%	43.1		%				41.7		%
	Sales and marketing	$	3,508		$	(303	)	$	3,205		$	10,812		$	(1,063	)	$	9,749
	The impact of this change in accounting principle was an increase to cost of revenue and a reduction to sales and marketing expense of $303,000 and $1,063,000 in the three and nine months ended December 31, 2013, respectively. Gross profit and gross profit percentage were reduced accordingly. The amount included in cost of sales that would have been included in sales and marketing historically, was $168,000 and $668,000 for the three and nine months ended December 31, 2014, respectively. The change had no effect on income from continuing operations, net income, earnings per share, or retained earnings for any period.
	Reclassifications
	In addition to the reclassification of shipping and handling costs disclosed above, certain amounts in the Condensed Consolidated Financial Statements for prior periods have been reclassified to reflect measurement period adjustments related to the CSI acquisition (See Note 2).

Acquisitions

Acquisitions	9 Months Ended
	Dec. 31, 2014
Business Combinations [Abstract]
Business Combination Disclosure [Text Block]	Acquisition
	CSI Acquisition
	On March 1, 2014, the Company's wholly-owned subsidiary, Westell, Inc. acquired 100% of the outstanding shares of CSI for a purchase price of $39.0 million in cash plus a $5.0 million working capital adjustment. CSI is an innovator of in-building wireless connectivity solutions for 3G/4G cellular services, enabling coverage anytime, anywhere. ClearLink, CSI’s high performance, low Passive Intermodulation Distortion (PIM) brand of in-building products are designed for distributed antenna systems and small cells. ClearLink products include Universal DAS Interface Trays (UDIT), passive DAS interface units, system components, and antennas. CSI’s portfolio also includes digital repeaters and E911 and location-based enhancement solutions for wireless networks.
	The Company incurred $39,000 and $0.2 million of related acquisition costs, which were expensed as incurred and reflected in general and administrative costs in the Condensed Consolidated Statement of Operations for the nine months ended December 31, 2014, and twelve months ended March 31, 2014, respectively.
	The results of CSI's operations have been included in the Condensed Consolidated Financial Statements since the date of acquisition and are reported within the In-Building Wireless (IBW) reporting segment (See Note 5). CSI contributed $5.1 million and $22.9 million to revenue and $2.4 million and $3.3 million to operating loss in the three and nine months ended December 31, 2014, respectively.
	In accordance with the acquisition method of accounting for business combinations, the Company allocated the total purchase consideration transferred to identifiable tangible and intangible assets acquired and liabilities assumed at the acquisition date based on each element’s estimated fair value with the remaining unallocated amounts recorded as goodwill. Purchased intangibles will be amortized over their respective estimated useful lives. Goodwill represents the expected synergies and other benefits from this acquisition that relates to the Company’s market position, customer relationships and supply chain capabilities. Goodwill recorded on the CSI acquisition is not expected to be amortized or deductible for U.S. federal and state income tax purposes. In the third quarter of fiscal year 2015, the Company performed an in interim evaluation of goodwill and concluded that the $20.5 million from the CSI acquisition, which was evaluated under the IBW reporting unit, was fully impaired (See Note 3.)
	The following table summarizes the fair value of the assets acquired and liabilities assumed as of the March 1, 2014, acquisition date:
	(in thousands)	Preliminary Amounts Recognized as of Acquisition			Measurement Period Adjustments				Final Amounts Recognized
		Date (1)
	Cash	$	6,513		$	—			$	6,513
	Accounts receivable	2,920			(20		)	(c)	2,900
	Inventories	7,625			(242		)	(c)	7,383
	Prepaid expenses and other current assets	158			(23		)	(c)	135
	Property and equipment	816			(45		)	(c)	771
	Intangible assets	16,230			(57		)	(a)	16,173
	Accounts payable, accruals and other liabilities	(2,875		)	(37		)	(c)	(2,912		)
	Income tax payable	(1,175		)	—				(1,175		)
	Deferred income tax liability	(6,616		)	323			(a)	(6,293		)
	Goodwill	20,142			405				20,547
	Total Consideration	$	43,738		$	304		(b)	$	44,042
	(1) As previously reported in the Notes to the Consolidated Financial Statements included in our 2014 Form 10-K.
	(a) Intangible asset fair value adjustment for trade name and related tax effect
	(b) Payment for final working capital adjustment
	(c) Other measurement period adjustments mostly related to inventory adjustments
	Under ASC 805, Business Combinations, the Company is required to recognize adjustments to provisional amounts during the measurement period as they are identified, and to recognize such adjustments retrospectively, as if the accounting for the business combination had been completed at the acquisition date. The March 31, 2014, balance sheet has been adjusted to reflect the measurement period adjustments, including the working capital adjustment which was included in accounts payable.
	The following table summarizes the acquired identified intangible assets, the respective fair value, and estimated useful life at the date of acquisition:
	(in thousands)		Fair Value			Estimated Life
	Backlog		$	90		1 month
	Customer relationships		11,410			9 years
	Trademark		303			1 year
	Developed technology		3,860			3 years
	Non-compete		510			2 years
	Total intangible assets		$	16,173
	The following unaudited summary information is presented on a consolidated pro forma basis as if the CSI acquisition had occurred on April 1, 2012. The pro forma amounts reflect the accounting effects of the business combination, including the application of the Company's accounting policies, amortization of intangible assets based on the estimated fair value and the impact of other fair value purchase accounting impacts such as inventory valuation step-up. The pro forma results are based on historical information and is not necessarily indicative of the combined results had the acquisition been completed at April 1, 2012, nor are they indicative of future combined results.
	(in thousands)		Three months ended December 31, 2013			Nine months ended December 31, 2013
	Consolidated pro forma revenue		$	35,312		$	108,678
	Consolidated pro forma operating income		$	2,498		$	6,607

Goodwill_and_Intangibles_Goodw

Goodwill and Intangibles Goodwill and Intangibles	9 Months Ended
	Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets Disclosure [Text Block]	Goodwill and Intangible Assets
	The Company has recorded intangible assets, such as goodwill, trademark, developed technology, non-compete agreements, backlog, and customer relationships, and accounts for these in accordance with ASC 350, Intangibles-Goodwill and Other (ASC 350). ASC 350 requires an annual test of goodwill and indefinite-lived assets for impairment, unless circumstances dictate more frequent assessments.
	During fiscal year 2015, the Company experienced triggering events in the second and third quarters that resulted in the Company testing its goodwill for impairment. In the second quarter, continued deterioration in macroeconomic conditions, decline in market capitalization, continued operating losses, lower forecasted revenue and cash flows, and the overall decline in the Company’s net sales during the quarter, indicated that it was more likely than not that the fair value of certain reporting units was reduced to below the respective carrying amount. As a result, in connection with the preparation of the financial statements for the quarter ended September 30, 2014, the Company considered these factors as a triggering event and performed an interim evaluation of goodwill using a two-step quantitative assessment. The first step compared the fair value of the reporting units with the carrying value as of September 1, 2014. The IBW reporting unit's fair value was approximately 13% greater than its carrying value at that time. The IBW reporting unit had a goodwill balance of $20.5 million as of September 30, 2014. The CSG reporting unit's fair value was below its carrying value therefore the Company completed the second step of the evaluation, which compares the implied fair value of goodwill with the carrying value of goodwill to determine the amount of the impairment loss. Fair value of the reporting unit was determined using a combination of income and market approaches. Determining the fair value of the reporting unit and the allocation of that fair value to individual assets and liabilities within the reporting unit to determine the implied fair value of the goodwill is judgmental in nature and requires the use of significant estimates and assumptions. These estimates and assumptions include discount rate, terminal growth rate, selection of peer group companies and control premium applied as well as forecasts of revenue growth rates, gross margins, operating margins, and working capital requirements. The allocation requires analysis to determine the fair value of assets and liabilities including, among others, customer relationships, trade names, and property and equipment. Any changes in the judgments, estimates, or assumptions used could produce significantly different results. As a result of that goodwill impairment evaluation, a goodwill impairment charge of $10.6 million was recorded in the quarter ended September 30, 2014. This charge was comprised of 100% of the goodwill for the CSG segment.
	During the third quarter ended December 31, 2014, due to the continuing decline in the market price of the Company’s stock, the market capitalization of the Company fell farther below the carrying value, indicating the need to perform another interim evaluation of goodwill. As a result, in connection with preparation of the financial statements for the quarter ended December 31, 2014, the Company considered these factors as a triggering event and performed an interim evaluation of goodwill using a two-step quantitative assessment. The first step compared the fair value of the IBW reporting unit with the carrying value as of December 31, 2014, and determined that the unit's fair value was below its carrying value. Due to the timing and complexity of the second step of the evaluation, which is required to determine the actual impairment, the Company was unable to finalize the amount of the impairment prior to the filing of form 10-Q for the quarter ended December 31, 2014. The Company will finalize the second step of the goodwill assessment in the quarter ended March 31, 2015, but has estimated that the goodwill related to the IBW segment is fully impaired and recorded an impairment charge of $20.5 million in the third quarter ended December 31, 2014.
	The following table is a summary of the goodwill balance for each reporting unit of December 31, 2014:
		Kentrox			CSI			CSG			IBW			Total
	Adjusted net goodwill as of March 31, 2014	$10,555			$20,547			$	—		$	—		$31,102
	First quarter fiscal 2015 change in reporting units	(10,555		)	(20,547		)	10,555			20,547			—
	Second quarter fiscal 2015 impairment charge	—			—			(10,555		)	—			(10,555		)
	Third quarter fiscal 2015 impairment charge	—			—			—			(20,547		)	(20,547		)
	Net goodwill as of December 31, 2014	$	—		$	—		$	—		$	—		$	—
	Intangible assets include customer relationships, trade names, developed technology and other intangibles. Intangible assets with determinable lives are amortized over the estimated useful lives of the assets. These intangible assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Determination of recoverability is based on an estimate of undiscounted future cash flows resulting from the use of the asset and its eventual disposition. If the carrying amount of an asset exceeds its estimated future undiscounted cash flows, an impairment loss is recorded for the excess of the asset’s carrying amount over its fair value. In the second and third quarters of fiscal 2015 due to the indications of impairment noted above, the Company reviewed finite-lived assets for impairment. The second quarter review resulted in a $0.1 million impairment loss in the CSG segment. No impairment was found in the third quarter review.

Restructuring_Charge

Restructuring Charge	9 Months Ended
	Dec. 31, 2014
Restructuring Charges [Abstract]
Restructuring Charge	Restructuring Charge
	In the first quarter of fiscal year 2014, the Company acquired Kentrox and identified redundant employees who exited the business after a period of time. The Company recognized no restructuring expense in the three months ended December 31, 2014. The Company recognized a restructuring expense of $55,000 in the nine months ended December 31, 2014 and restructuring expense of $38,000 and $273,000 in the three and nine months ended December 31, 2013, respectively, for severance for these transitional employees. The total cost of this action was $390,000. As of March 31, 2014, $57,000 was unpaid and accrued on the Condensed Consolidated Balance Sheets within Accrued compensation.
	Total restructuring charges and their utilization for the nine months ended December 31, 2014, and 2013, are summarized as follows:
		Nine months ended December 31, 2014			Nine months ended December 31, 2013
	(in thousands)	Employee-related			Employee-related
	Liability at beginning of period	$	57		$	6
	Charged	55			273
	Paid	(112		)	(202		)
	Liability at end of period	$	—		$	77

Interim_Segment_Information

Interim Segment Information	9 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Interim Segment Information	Interim Segment Information
	Westell’s Chief Executive Officer is the chief operating decision maker (CODM). In the first quarter of fiscal 2015, the Company revised its segment reporting structure to realign internal reporting as a result of the full integration of Kentrox into Westell, and the recent CSI acquisition. The CODM continues to define segment profit as gross profit less research and development expenses. In order to provide information that is comparable year to year, fiscal year 2014 segment information has been restated to reflect the new reporting structure. The accounting policies of the segments are the same as those for Westell Technologies, Inc. described in the summary of significant accounting policies.
	The Company’s two reportable segments are as follows:
	Communication Solutions Group (CSG) Segment
	The CSG segment consists of all the intelligent site management, cell site optimization, and outside plant solutions product offerings. CSG segment products and solutions are developed at the Company’s design centers in Dublin, Ohio; Aurora, Illinois; and Regina, Canada. The CSG operations are managed centrally at the Aurora facility, where products are assembled, tested, packaged, and shipped to customers.
	In-Building Wireless (IBW) Segment
	The IBW segment consists of all the in-building wireless solutions products, which include the comprehensive suite of products and solutions acquired with the addition of CSI, as well as the Westell developed DAS interface panels. IBW segment products and solutions are developed at the Company’s design center in Manchester, New Hampshire. IBW operations are managed centrally at our Manchester facility, where products other than the Westell developed DAS panels, are assembled, tested, packaged, and shipped to customers. The Westell developed DAS panels are assembled, tested, packaged, and shipped from Aurora, Illinois.
	Segment information for the three and nine months ended December 31, 2014, and 2013 is set forth below:
		Three months ended December 31, 2014
	(in thousands)	CSG			IBW			Total
	Revenue	$	8,629		$	5,414		$	14,043
	Cost of revenue	6,144			3,504			9,648
	Gross profit	2,485			1,910			4,395
	Gross margin	28.8		%	35.3		%	31.3		%
	Research and development	2,011			2,342			4,353
	Segment profit (loss)	$	474		$	(432	)	42
	Operating expenses:
	Sales and marketing							2,719
	General and administrative							2,797
	Intangible amortization							1,562
	Goodwill impairment							20,547
	Operating income (loss)							(27,583		)
	Other income (expense), net							(29		)
	Income tax benefit (expense)							72
	Net income (loss) from continuing operations							$	(27,540	)
		Three months ended December 31, 2013
	(in thousands)	CSG			IBW			Total
	Revenue	$	23,425		$	1,811		$	25,236
	Cost of revenue	12,037			1,267			13,304
	Gross profit	11,388			544			11,932
	Gross margin	48.6		%	30		%	47.3		%
	Research and development	2,347			180			2,527
	Segment profit	$	9,041		$	364		9,405
	Operating expenses:
	Sales and marketing							3,205
	General and administrative							3,402
	Intangible amortization							737
	Restructuring							38
	Operating income (loss)							2,023
	Other income (expense), net							(31		)
	Income tax benefit (expense)							(38		)
	Net income (loss) from continuing operations							$	1,954
		Nine months ended December 31, 2014
	(in thousands)	CSG			IBW			Total
	Revenue	$	34,882		$	30,632		$	65,514
	Cost of revenue	24,827			18,543			43,370
	Gross profit	10,055			12,089			22,144
	Gross margin	28.8		%	39.5		%	33.8		%
	Research and development	6,488			6,640			13,128
	Segment profit	$	3,567		$	5,449		9,016
	Operating expenses:
	Sales and marketing							9,064
	General and administrative							9,131
	Intangible amortization							4,857
	Restructuring							55
	Goodwill impairment							31,102
	Operating income (loss)							(45,193		)
	Other income (expense), net							16
	Income tax benefit (expense)							170
	Net income (loss) from continuing operations							$	(45,007	)
		Nine months ended December 31, 2013
	(in thousands)	CSG			IBW			Total
	Revenue	$	72,774		$	4,878		$	77,652
	Cost of revenue	41,977			3,304			45,281
Gross profit	30,797			1,574			32,371
Gross margin	42.3		%	32.3		%	41.7		%
Research and development	7,292			553			7,845
Segment profit	$	23,505		$	1,021		24,526
Operating expenses:
Sales and marketing							9,749
General and administrative							10,200
Intangible amortization							3,588
Restructuring							273
Operating income (loss)							716
Other income (expense), net							(63		)
Income tax benefit (expense)							(125		)
Net income (loss) from continuing operations							$	528
Asset information, although available, is not reported to or used by the CODM.

Inventories

Inventories	9 Months Ended
	Dec. 31, 2014
Inventory, Net [Abstract]
Inventories	Inventories
	Inventories are stated at the lower of first-in, first-out cost or market value. The components of inventories are as follows:
	(in thousands)	December 31, 2014		31-Mar-14
	Raw materials	$	7,518	$	9,076
	Finished goods and sub-assemblies	15,391		14,980
	Total inventories	$	22,909	$	24,056

StockBased_Compensation

Stock-Based Compensation	9 Months Ended
	Dec. 31, 2014
Share-based Compensation [Abstract]
Stock-Based Compensation	Stock-Based Compensation
	The following table is a summary of total stock-based compensation resulting from stock options, restricted stock, restricted stock units (RSUs) and performance stock units (PSUs), during the three and nine months ended December 31, 2014, and 2013:
		Three months ended December 31,						Nine months ended December 31,
	(in thousands)	2014			2013			2014			2013
	Stock-based compensation expense	$	514		$	553		$	1,628		$	1,293
	Income tax expense	—			—			—			—
	Total stock-based compensation expense after taxes	$	514		$	553		$	1,628		$	1,293
	The stock options, restricted stock awards, and RSUs awarded in the nine months ended December 31, 2014, vest in equal annual installments over four years. PSUs earned vest over the performance period, as described below. On September 16, 2014, the Board of Directors modified the vesting provisions on all outstanding non-employee director restricted stock awards to include an accelerated vesting provision triggered upon a termination of service as a director following a failure to be nominated by the Board of Directors for re-election as a director. As a result of that modification, the requisite service period on all unvested restricted stock was shortened to the next expected nomination date in July 2015. As a result of this modification, the Company recorded incremental stock-based compensation expense of $70,000 and $158,000 during the three and nine months ended December 31, 2014.
	Stock Options
	Stock option activity for the nine months ended December 31, 2014, is as follows:
		Shares		Weighted-Average			Weighted-Average		Aggregate
				Exercise Price Per			Remaining		Intrinsic Value (a) (in
				Share			Contractual Term		thousands)
							(in years)
	Outstanding on March 31, 2014	1,835,445		$	2.02		3.7		$	3,110
	Granted	40,000		3.47
	Exercised	(69,200	)	2.24
	Forfeited	(212,500	)	2.56
	Expired	(252,430	)	2.68
	Outstanding on December 31, 2014	1,341,315		$	1.84		3.2		$	417
	(a)	The intrinsic value for the stock options is calculated based on the difference between the exercise price of the underlying awards and the average of the high and low Westell Technologies’ stock price as of the reporting date.
	The weighted-average fair value of stock options granted during the nine months ended December 31, 2014, was $1.27 per share.
	Restricted Stock
	The following table sets forth restricted stock activity for the nine months ended December 31, 2014:
		Shares		Weighted-Average
				Grant Date Fair
				Value
	Non-vested as of March 31, 2014	407,500		$	1.94
	Granted	100,000		3.53
	Vested	(337,500	)	1.89
	Forfeited	—		—
	Non-vested as of December 31, 2014	170,000		$	2.98
	RSUs
	The following table sets forth the RSU activity for the nine months ended December 31, 2014:
		Shares		Weighted-Average
				Grant Date Fair
				Value
	Non-vested as of March 31, 2014	1,679,000		$	3.09
	Granted	524,500		2.7
	Vested	(387,500	)	2.67
	Forfeited	(364,750	)	2.72
	Non-vested as of December 31, 2014	1,451,250		$	3.15
	PSUs
	The PSUs vest in annual increments based on the achievement of pre-established Company performance goals and continued employment. The number of PSUs earned, if any, can range from 0% to 200% of the target amount, depending on actual performance for four fiscal years following the grant date. Upon vesting, the PSUs convert into shares of Class A Common Stock on a one-for-one basis.
	The following table sets forth the PSU activity for the nine months ended December 31, 2014:
		Shares		Weighted-Average Grant Date Fair Value
	Non-vested as of March 31, 2014	285,000		$	2.45
	Granted, at target	217,500		3.83
	Vested	(66,764	)	2.45
	Forfeited	(102,431	)	3.04
	Non-vested as of December 31, 2014	333,305		$	3.16

Product_Warranties

Product Warranties	9 Months Ended
	Dec. 31, 2014
Product Warranties Disclosures [Abstract]
Product Warranties	Product Warranties
	The Company’s products carry a limited warranty ranging from one to seven years for the products within the CSG segment and one to five years for products within the IBW segment. The specific terms and conditions of those warranties vary depending upon the customer and the products sold. Factors that enter into the estimate of the Company’s warranty reserve include: the number of units shipped, anticipated rates of warranty claims, and cost per claim. The Company periodically assesses the adequacy of its recorded warranty liability and adjusts the reserve as necessary. The current portions of the warranty reserve were $549,000 and $286,000 as of December 31, 2014, and March 31, 2014, respectively, and are presented on the Condensed Consolidated Balance Sheets as Accrued expenses. The non-current portions of the warranty reserve were $146,000 and $42,000 as of December 31, 2014, and March 31, 2014, respectively, and are presented on the Condensed Consolidated Balance Sheets in Other non-current liabilities.
	The following table presents the changes in the Company’s product warranty reserve:
		Three months ended December 31,						Nine months ended December 31,
	(in thousands)	2014			2013			2014			2013
	Total product warranty reserve at the beginning of the	$	666		$	325		$	328		$	152
	period
	Warranty reserve assumed from business acquisitions	—			—			—			54
	Warranty expense to cost of revenue	64			73			474			343
	Utilization	(35		)	(41		)	(107		)	(192		)
	Total product warranty reserve at the end of the period	$	695		$	357		$	695		$	357

Variable_Interest_Entity_and_G

Variable Interest Entity and Guarantee	9 Months Ended
	Dec. 31, 2014
Guarantees [Abstract]
Equity Method Investment [Text Block]	Variable Interest Entity and Guarantee
	The Company has a 50% equity ownership in AccessTel Kentrox Australia PTY LTD (AKA). AKA distributes network management solutions provided by the Company and the other 50% owner to one customer. The Company holds equal voting control with the other owner. All actions of AKA are decided at the board level by majority vote. The Company evaluated ASC 810, Consolidations, and concluded that AKA is a variable interest entity (VIE). The Company has concluded that it is not the primary beneficiary of AKA and therefore consolidation is not required. As of December 31, 2014, and March 31, 2014, the carrying amount of the Company's investment in AKA was approximately $74,000 and $84,000, respectively, which is presented on the Condensed Consolidated Balance Sheets within Other non-current assets.
	The Company's revenue from sales to AKA for the three and nine months ended December 31, 2014 was $0.3 million and $1.4 million, respectively. The Company's revenue from sales to AKA for the three and nine months ended December 31, 2013, was $1.3 million and $3.9 million, respectively. Accounts receivable from AKA was $0.2 million and $0.4 million as of December 31, 2014, and March 31, 2014, respectively. Deferred revenue relating to AKA maintenance contracts was $1.1 million as of December 31, 2014, and $1.0 million as of March 31, 2014. The Company also has an unlimited guarantee for the performance of the other 50% owner in AKA, which primarily provides support and engineering services to the customer. This guarantee was put in place at the request of the AKA customer. The guarantee, which is estimated to have a maximum potential future payment of $0.7 million, will stay in place as long as the contract between AKA and the customer is in place. The Company would have recourse against the other 50% owner in AKA in the event the guarantee is triggered. The Company determined that it could perform on the obligation it guaranteed at a positive rate of return and therefore did not assign value to the guarantee. The Company's exposure to loss as a result of its involvement with AKA, exclusive of lost profits, is limited to the items noted above.

Income_Taxes

Income Taxes	9 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes
	At the end of each interim period, the Company makes its best estimate of the effective tax rate expected to be applicable for the full fiscal year and uses that rate to provide for income taxes on a current year-to-date basis before discrete items. If a reliable estimate cannot be made, the Company may make a reasonable estimate of the annual effective tax rate, including use of the actual effective rate for the year-to-date. The impact of discrete items is recorded in the quarter in which they occur. The Company utilizes the liability method of accounting for income taxes and deferred taxes which are determined based on the differences between the financial statements and tax basis of assets and liabilities given the enacted tax laws. The Company evaluates the need for valuation allowances on the net deferred tax assets under the rules of ASC 740, Income Taxes. In assessing the realizability of the Company's deferred tax assets, the Company considered whether it is more likely than not that some or all of the deferred tax assets will be realized through the generation of future taxable income. In making this determination, the Company assessed all of the evidence available at the time including recent earnings, forecasted income projections and historical performance. In fiscal year 2013, the Company determined that the negative evidence outweighed the objectively verifiable positive evidence and recorded a full valuation allowance against deferred tax assets. The Company will continue to reassess realizability going forward.
	The Company recorded $72,000 and $170,000 of income tax benefit in the three and nine months ended December 31, 2014, using an effective income tax rate of 0.3% and 0.4%, respectively. The Company recorded $38,000 and $125,000 of income tax expense in the three and nine months ended December 31, 2013, using an effective rate of 1.9% and 19.1%, respectively. The effective rate is impacted by states which base tax on gross margin and not pre-tax income.

Commitments_and_Contingencies

Commitments and Contingencies	9 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies
	Obligations
	Future obligations and commitments, which are comprised of future minimum lease payments, inventory purchase obligations, and contingent consideration, decreased $8.4 million in the nine months ended December 31, 2014, to $15.3 million, from $23.7 million at March 31, 2014. This decrease included a $1.1 million payment of contingent consideration.
	Purchase obligations consist of inventory that arises in the normal course of business operations. Future obligations and commitments as of December 31, 2014, consisted of the following:
		Payments due within
	(in thousands)	Year 1		Year 2		Year 3		Year 4		Year 5		Thereafter		Total
	Purchase obligations	$	5,865	$	—	$	—	$	—	$	—	$	—	$	5,865
	Future minimum operating lease	3,189		2,695		1,597		280		87		—		7,848
	payments
	Contingent consideration	727		811		—		—		—		—		1,538
	Future obligations and	$	9,781	$	3,506	$	1,597	$	280	$	87	$	—	$	15,251
	commitments
	Litigation and Contingency Reserves
	The Company and its subsidiaries are involved in various assertions, claims, proceedings and requests for indemnification concerning intellectual property, including patent infringement suits involving technologies that may be incorporated in the Company’s products, which are being handled and defended in the ordinary course of business.  These matters are in various stages of investigation and litigation, and they are being vigorously defended.  Although the Company does not expect that the outcome in any of these matters, individually or collectively, will have a material adverse effect on its financial condition or results of operations, litigation is inherently unpredictable.  Therefore, judgments could be rendered, or settlements entered, that could adversely affect the Company’s operating results or cash flows in a particular period. The Company routinely assesses all of its litigation and threatened litigation as to the probability of ultimately incurring a liability, and it records its best estimate of the ultimate loss in situations where it assesses the likelihood of loss as probable. As of December 31, 2014, and March 31, 2014, the Company has not recorded any contingent liability attributable to existing litigation.
	As of December 31, 2014, and March 31, 2014, the Company had total contingency reserves of $0.7 million, related to the discontinued operations of ConferencePlus which was sold in fiscal year 2012. The contingency reserves are classified as Accrued expenses on the Consolidated Balance Sheets. In fiscal year 2014, the Company paid $1.1 million relating to a ConferencePlus indemnification claim.
	Additionally, the Company has a contingent cash consideration payable related to an acquisition.  The contingent consideration becomes payable based upon the profitability of the acquired products for post-closing periods through June 30, 2016, and is offset by working capital adjustments and other indemnification claims. The maximum earn-out that could be paid before offsets is $3.5 million. As of December 31, 2014, and March 31, 2014, the fair value of the contingent consideration liability after offsetting a working capital adjustment and an indemnification claim for warranty obligations was $1.5 million and $2.6 million, respectively (See Note 13).

Shortterm_Investments

Short-term Investments	9 Months Ended
	Dec. 31, 2014
Short-term Investments [Abstract]
Short-term Investments	Short-term Investments
	The following table presents short-term investments as of December 31, 2014, and March 31, 2014:
	(in thousands)	December 31, 2014		March 31, 2014
	Certificates of deposit	$	8,413	$	1,476
	Held-to-maturity, pre-refunded municipal bonds	16,809		14,108
	Total short-term investments	$	25,222	$	15,584
	The fair value of investments approximates their carrying amounts due to the short-term nature of these financial assets.

Fair_Value_Measurements

Fair Value Measurements	9 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements
	Fair value is defined by ASC 820, Fair Value Measurements and Disclosures (ASC 820), as the price that would be received upon selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. ASC 820 establishes a three-level fair value hierarchy that prioritizes the inputs used to measure fair value. The hierarchy requires entities to maximize the use of observable inputs and minimize the use of unobservable inputs. The three levels of inputs used to measure fair value are as follows:
	•	Level 1 – Quoted prices in active markets for identical assets and liabilities.
	•	Level 2 – Quoted prices in active markets for similar assets and liabilities, or other inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the financial instrument.
	•	Level 3 – Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets and liabilities. This includes certain pricing models, discounted cash flow methodologies and similar techniques that use significant unobservable inputs.
	The Company’s money market funds are measured using Level 1 inputs. The contingent consideration described in Note 11 is measured using Level 3 inputs.
	The following table presents financial assets and non-financial liabilities measured at fair value on a recurring basis and their related valuation inputs as of December 31, 2014:
	(in thousands)	Total Fair Value			Quoted Prices in			Significant Other	Significant		Balance Sheet
		of Asset or			Active Markets			Observable Inputs	Unobservable		Classification
		Liability			for Identical Assets			(Level 2)	Inputs
					(Level 1)				(Level 3)
	Assets:
	Money market funds	$	2,111		$	2,111		—	—		Cash and cash
											equivalents
	Liabilities:
	Contingent consideration, current	$	727		—			—	$	727	Contingent
											consideration
	Contingent consideration, non-	$	811		—			—	$	811	Contingent consideration non-current
	current
	The following table presents financial assets and liabilities measured at fair value on a recurring basis and their related valuation inputs as of March 31, 2014:
	(in thousands)	Total Fair Value			Quoted Prices in			Significant Other	Significant		Balance Sheet
		of Asset or			Active Markets			Observable Inputs	Unobservable		Classification
		Liability			for Identical Assets			(Level 2)	Inputs
					(Level 1)				(Level 3)
	Assets:
	Money market funds	$	117		$	117		—	—		Cash and cash
											equivalents
	Liabilities:
	Contingent consideration, current	$	2,067		—			—	$	2,067	Contingent consideration
	Contingent consideration, non-	$	574		—			—	$	574	Contingent
	current										consideration
											non-current
	The fair value of the money market funds approximates their carrying amounts due to the short-term nature of these financial assets.
	In connection with an acquisition in the quarter ended June 30, 2012, payment of a portion of the purchase price is contingent upon the profitability of the acquired products for post-closing periods through June 30, 2016, and may be offset by working capital adjustments and other indemnification claims. The Company estimates the fair value of contingent consideration as the present value of the expected payments over the term of the arrangement based on financial forecasts of future profitability of the acquired products, and reaching the forecast. This estimate is subject to ongoing evaluation. Inputs such as forecasted revenue for the acquired products and acquired product profitability are the most significant drivers of the fair value measurement and are based on full attainment. Significant decreases in any of those inputs would result in a significantly lower fair value measurement. The actual cash payment could range from $1.1 million to $2.7 million.
	The fair value measurement of contingent consideration as of December 31, 2014, and March 31, 2014, encompasses the following significant unobservable inputs:
	($ in thousands)	Unobservable Inputs
		31-Dec-14			31-Mar-14
	Estimated earn-out contingent consideration	$	3,500		$	3,500
	Working capital and other adjustment	(444		)	(444		)
	Indemnification related to warranty claims	(303		)	(303		)
	Discount rate	7.4		%	7.5		%
	Approximate timing of cash flows	1.6 years			1.4 years
	The following table summarizes contingent consideration activity:
	(in thousands)
	Balance as of March 31, 2014	$	2,641
	Contingent consideration – payments	(1,104		)
	Contingent consideration – change in fair value in G&A expense	1
	Balance as of December 31, 2014	$	1,538

Share_Repurchases

Share Repurchases	9 Months Ended
	Dec. 31, 2014
Payments for Repurchase of Equity [Abstract]
Share Repurchases	Share Repurchases
	In August 2011, the Board of Directors authorized a share repurchase program whereby the Company may repurchase up to an aggregate of $20.0 million of its outstanding Class A Common Stock (the "authorization”). There were no shares repurchased under this authorization during the nine months ended December 31, 2014, or December 31, 2013. There was approximately $0.1 million remaining for additional share repurchases under this program as of December 31, 2014.
	Additionally, in the nine months ended December 31, 2014, and 2013, the Company repurchased 219,518 and 152,874 shares of Class A Common Stock, respectively, from certain employees that were surrendered to satisfy the minimum statutory tax withholding obligations on the vesting of restricted stock, RSUs and PSUs. These repurchases are not included in the authorized share repurchase program and had a weighted-average purchase price of $3.16 and $2.08 per share, respectively.

Subsequent_Event_Notes

Subsequent Event (Notes)	9 Months Ended
	Dec. 31, 2014
Subsequent Event [Abstract]
Subsequent Events [Text Block]	Subsequent Event
	In the fourth quarter of fiscal 2015, the Company approved a plan to restructure its business, including a reduction of headcount and consolidation of office space within the Aurora headquarters facility. These actions, which are anticipated to be completed by March 31, 2015, are expected to result in a fourth quarter pre-tax charge currently estimated at $3.0 million.

Basis_of_Presentation_Policies

Basis of Presentation (Policies)	9 Months Ended
	Dec. 31, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Condensed consolidated financial statements	The accompanying Condensed Consolidated Financial Statements include the accounts of the Company and its wholly-owned subsidiaries. The Condensed Consolidated Financial Statements have been prepared using generally accepted accounting principles (GAAP) in the United States for interim financial reporting, and consistent with the instructions of Form 10-Q and Article 10 of Regulation S-X, and accordingly they do not include all of the information and footnotes required in the annual consolidated financial statements and accompanying footnotes. The Condensed Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements and accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended March 31, 2014. All intercompany accounts and transactions have been eliminated in consolidation.
Use of Estimates	Use of Estimates
	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, and that affect revenue and expenses during the periods reported. Estimates are used when accounting for the allowance for uncollectible accounts receivable, net realizable value of inventory, product warranty accrued, relative selling prices, stock-based compensation, goodwill and intangible assets fair value, depreciation, income taxes, and contingencies, among other things. Actual results could differ from those estimates.
New Accounting Pronouncements	Recently Issued Accounting Pronouncements
	In August 2014, the FASB issued ASU No. 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern (ASU 2014-15), to provide guidance on management’s responsibility in evaluating whether there is substantial doubt about a company’s ability to continue as a going concern and to provide related footnote disclosures. The amendments in this update are effective for the annual period ending after December 15, 2016, and for annual periods and interim periods thereafter. Early application is permitted. The Company does not expect the adoption of ASU 2014-15 to have a significant impact on its Consolidated Financial Statements or related disclosures.
	In May 2014, the FASB issued ASU No. 2014-09, Revenue From Contracts With Customers (ASU 2014-09), that outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. The ASU is based on the principle that an entity should recognize revenue to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The ASU also requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts, including significant judgments and changes in judgments and assets recognized from costs incurred to fulfill a contract. Entities have the option of using either a full retrospective or a modified retrospective approach for the adoption of the new standard. The ASU becomes effective for annual reporting periods beginning after December 15, 2016, including interim periods within that reporting period; early adoption is not permitted. The Company is currently assessing the impact that ASU 2014-09 will have on its Consolidated Financial Statements.
Shipping and Handling Cost	Effective April 1, 2014, the Company made a voluntary change in accounting principle to classify shipping and handling costs associated with the distribution of finished product to our customers as cost of revenue (previously recorded in sales and marketing expense). The Company made the voluntary change in principle because it believes the classification of shipping and handling costs in cost of revenue better reflects the cost of producing and distributing products. It also enhances the comparability of the financial statements with many industry peers. As required by U.S. generally accepted accounting principles, the change has been reflected in the Condensed Consolidated Statements of Operations through retrospective application of the change in accounting principle.
Inventory	Inventories are stated at the lower of first-in, first-out cost or market value.
Fair Value Measurement	Fair value is defined by ASC 820, Fair Value Measurements and Disclosures (ASC 820), as the price that would be received upon selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. ASC 820 establishes a three-level fair value hierarchy that prioritizes the inputs used to measure fair value. The hierarchy requires entities to maximize the use of observable inputs and minimize the use of unobservable inputs. The three levels of inputs used to measure fair value are as follows:
	•	Level 1 – Quoted prices in active markets for identical assets and liabilities.
	•	Level 2 – Quoted prices in active markets for similar assets and liabilities, or other inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the financial instrument.
	•	Level 3 – Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets and liabilities. This includes certain pricing models, discounted cash flow methodologies and similar techniques that use significant unobservable inputs.

Basis_of_Presentation_Basis_of

Basis of Presentation Basis of Presentation (Tables)	9 Months Ended
	Dec. 31, 2014
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block]	The following table provides the reconciliation from previously reported financial data as adjusted:
		Three months ended December 31, 2013									Nine months ended December 31, 2013
	(in thousands)	Previously reported			Effect of Accounting Principle Change			Adjusted			Previously reported			Effect of Accounting Principle Change			Adjusted
	Revenue	$	25,236		$	—		$	25,236		$	77,652		$	—		$	77,652
	Cost of revenue	13,001			303			13,304			44,218			1,063			45,281
	Gross profit	$	12,235		$	(303	)	$	11,932		$	33,434		$	(1,063	)	$	32,371
	Gross margin	48.5		%				47.3		%	43.1		%				41.7		%
	Sales and marketing	$	3,508		$	(303	)	$	3,205		$	10,812		$	(1,063	)	$	9,749

Acquisitions_Tables

Acquisitions (Tables)	9 Months Ended
	Dec. 31, 2014
Business Acquisition [Line Items]
Schedule of Purchase Price Allocation [Table Text Block]	The following table summarizes the fair value of the assets acquired and liabilities assumed as of the March 1, 2014, acquisition date:
	(in thousands)	Preliminary Amounts Recognized as of Acquisition			Measurement Period Adjustments				Final Amounts Recognized
		Date (1)
	Cash	$	6,513		$	—			$	6,513
	Accounts receivable	2,920			(20		)	(c)	2,900
	Inventories	7,625			(242		)	(c)	7,383
	Prepaid expenses and other current assets	158			(23		)	(c)	135
	Property and equipment	816			(45		)	(c)	771
	Intangible assets	16,230			(57		)	(a)	16,173
	Accounts payable, accruals and other liabilities	(2,875		)	(37		)	(c)	(2,912		)
	Income tax payable	(1,175		)	—				(1,175		)
	Deferred income tax liability	(6,616		)	323			(a)	(6,293		)
	Goodwill	20,142			405				20,547
	Total Consideration	$	43,738		$	304		(b)	$	44,042
Schedule of Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table Text Block]	The following table summarizes the acquired identified intangible assets, the respective fair value, and estimated useful life at the date of acquisition:
	(in thousands)		Fair Value			Estimated Life
	Backlog		$	90		1 month
	Customer relationships		11,410			9 years
	Trademark		303			1 year
	Developed technology		3,860			3 years
	Non-compete		510			2 years
	Total intangible assets		$	16,173
Business Acquisition, Pro Forma Information [Table Text Block]	The following unaudited summary information is presented on a consolidated pro forma basis as if the CSI acquisition had occurred on April 1, 2012. The pro forma amounts reflect the accounting effects of the business combination, including the application of the Company's accounting policies, amortization of intangible assets based on the estimated fair value and the impact of other fair value purchase accounting impacts such as inventory valuation step-up. The pro forma results are based on historical information and is not necessarily indicative of the combined results had the acquisition been completed at April 1, 2012, nor are they indicative of future combined results.
	(in thousands)		Three months ended December 31, 2013			Nine months ended December 31, 2013
	Consolidated pro forma revenue		$	35,312		$	108,678
	Consolidated pro forma operating income		$	2,498		$	6,607

Goodwill_and_Intangibles_Goodw1

Goodwill and Intangibles Goodwill and Intangibles (Tables)	9 Months Ended
	Dec. 31, 2014
Goodwill [Line Items]
Schedule of Goodwill [Table Text Block]	The following table is a summary of the goodwill balance for each reporting unit of December 31, 2014:
		Kentrox			CSI			CSG			IBW			Total
	Adjusted net goodwill as of March 31, 2014	$10,555			$20,547			$	—		$	—		$31,102
	First quarter fiscal 2015 change in reporting units	(10,555		)	(20,547		)	10,555			20,547			—
	Second quarter fiscal 2015 impairment charge	—			—			(10,555		)	—			(10,555		)
	Third quarter fiscal 2015 impairment charge	—			—			—			(20,547		)	(20,547		)
	Net goodwill as of December 31, 2014	$	—		$	—		$	—		$	—		$	—

Restructuring_Charge_Tables

Restructuring Charge (Tables)	9 Months Ended
	Dec. 31, 2014
Restructuring Charges [Abstract]
Restructuring charges	Total restructuring charges and their utilization for the nine months ended December 31, 2014, and 2013, are summarized as follows:
		Nine months ended December 31, 2014			Nine months ended December 31, 2013
	(in thousands)	Employee-related			Employee-related
	Liability at beginning of period	$	57		$	6
	Charged	55			273
	Paid	(112		)	(202		)
	Liability at end of period	$	—		$	77

Interim_Segment_Information_Ta

Interim Segment Information (Tables)	9 Months Ended
	Dec. 31, 2014
Segment Reporting [Abstract]
Segment information	Segment information for the three and nine months ended December 31, 2014, and 2013 is set forth below:
		Three months ended December 31, 2014
	(in thousands)	CSG			IBW			Total
	Revenue	$	8,629		$	5,414		$	14,043
	Cost of revenue	6,144			3,504			9,648
	Gross profit	2,485			1,910			4,395
	Gross margin	28.8		%	35.3		%	31.3		%
	Research and development	2,011			2,342			4,353
	Segment profit (loss)	$	474		$	(432	)	42
	Operating expenses:
	Sales and marketing							2,719
	General and administrative							2,797
	Intangible amortization							1,562
	Goodwill impairment							20,547
	Operating income (loss)							(27,583		)
	Other income (expense), net							(29		)
	Income tax benefit (expense)							72
	Net income (loss) from continuing operations							$	(27,540	)
		Three months ended December 31, 2013
	(in thousands)	CSG			IBW			Total
	Revenue	$	23,425		$	1,811		$	25,236
	Cost of revenue	12,037			1,267			13,304
	Gross profit	11,388			544			11,932
	Gross margin	48.6		%	30		%	47.3		%
	Research and development	2,347			180			2,527
	Segment profit	$	9,041		$	364		9,405
	Operating expenses:
	Sales and marketing							3,205
	General and administrative							3,402
	Intangible amortization							737
	Restructuring							38
	Operating income (loss)							2,023
	Other income (expense), net							(31		)
	Income tax benefit (expense)							(38		)
	Net income (loss) from continuing operations							$	1,954
		Nine months ended December 31, 2014
	(in thousands)	CSG			IBW			Total
	Revenue	$	34,882		$	30,632		$	65,514
	Cost of revenue	24,827			18,543			43,370
	Gross profit	10,055			12,089			22,144
	Gross margin	28.8		%	39.5		%	33.8		%
	Research and development	6,488			6,640			13,128
	Segment profit	$	3,567		$	5,449		9,016
	Operating expenses:
	Sales and marketing							9,064
	General and administrative							9,131
	Intangible amortization							4,857
	Restructuring							55
	Goodwill impairment							31,102
	Operating income (loss)							(45,193		)
	Other income (expense), net							16
	Income tax benefit (expense)							170
	Net income (loss) from continuing operations							$	(45,007	)
		Nine months ended December 31, 2013
	(in thousands)	CSG			IBW			Total
	Revenue	$	72,774		$	4,878		$	77,652
	Cost of revenue	41,977			3,304			45,281
	Gross profit	30,797			1,574			32,371
	Gross margin	42.3		%	32.3		%	41.7		%
	Research and development	7,292			553			7,845
	Segment profit	$	23,505		$	1,021		24,526
	Operating expenses:
	Sales and marketing							9,749
	General and administrative							10,200
Intangible amortization							3,588
Restructuring							273
Operating income (loss)							716
Other income (expense), net							(63		)
Income tax benefit (expense)							(125		)
Net income (loss) from continuing operations							$	528

Inventories_Tables

Inventories (Tables)	9 Months Ended
	Dec. 31, 2014
Inventory, Net [Abstract]
Components of inventories	Inventories are stated at the lower of first-in, first-out cost or market value. The components of inventories are as follows:
	(in thousands)	December 31, 2014		31-Mar-14
	Raw materials	$	7,518	$	9,076
	Finished goods and sub-assemblies	15,391		14,980
	Total inventories	$	22,909	$	24,056

StockBased_Compensation_Tables

Stock-Based Compensation (Tables)	9 Months Ended
	Dec. 31, 2014
Share-based Compensation [Abstract]
Stock-based compensation expense	The following table is a summary of total stock-based compensation resulting from stock options, restricted stock, restricted stock units (RSUs) and performance stock units (PSUs), during the three and nine months ended December 31, 2014, and 2013:
		Three months ended December 31,						Nine months ended December 31,
	(in thousands)	2014			2013			2014			2013
	Stock-based compensation expense	$	514		$	553		$	1,628		$	1,293
	Income tax expense	—			—			—			—
	Total stock-based compensation expense after taxes	$	514		$	553		$	1,628		$	1,293
Stock option activity	Stock option activity for the nine months ended December 31, 2014, is as follows:
		Shares		Weighted-Average			Weighted-Average		Aggregate
				Exercise Price Per			Remaining		Intrinsic Value (a) (in
				Share			Contractual Term		thousands)
							(in years)
	Outstanding on March 31, 2014	1,835,445		$	2.02		3.7		$	3,110
	Granted	40,000		3.47
	Exercised	(69,200	)	2.24
	Forfeited	(212,500	)	2.56
	Expired	(252,430	)	2.68
	Outstanding on December 31, 2014	1,341,315		$	1.84		3.2		$	417
	(a)	The intrinsic value for the stock options is calculated based on the difference between the exercise price of the underlying awards and the average of the high and low Westell Technologies’ stock price as of the reporting date.
Restricted stock activity	Restricted Stock
	The following table sets forth restricted stock activity for the nine months ended December 31, 2014:
		Shares		Weighted-Average
				Grant Date Fair
				Value
	Non-vested as of March 31, 2014	407,500		$	1.94
	Granted	100,000		3.53
	Vested	(337,500	)	1.89
	Forfeited	—		—
	Non-vested as of December 31, 2014	170,000		$	2.98
	RSUs
	The following table sets forth the RSU activity for the nine months ended December 31, 2014:
		Shares		Weighted-Average
				Grant Date Fair
				Value
	Non-vested as of March 31, 2014	1,679,000		$	3.09
	Granted	524,500		2.7
	Vested	(387,500	)	2.67
	Forfeited	(364,750	)	2.72
	Non-vested as of December 31, 2014	1,451,250		$	3.15
	PSUs
	The PSUs vest in annual increments based on the achievement of pre-established Company performance goals and continued employment. The number of PSUs earned, if any, can range from 0% to 200% of the target amount, depending on actual performance for four fiscal years following the grant date. Upon vesting, the PSUs convert into shares of Class A Common Stock on a one-for-one basis.
	The following table sets forth the PSU activity for the nine months ended December 31, 2014:
		Shares		Weighted-Average Grant Date Fair Value
	Non-vested as of March 31, 2014	285,000		$	2.45
	Granted, at target	217,500		3.83
	Vested	(66,764	)	2.45
	Forfeited	(102,431	)	3.04
	Non-vested as of December 31, 2014	333,305		$	3.16

Product_Warranties_Tables

Product Warranties (Tables)	9 Months Ended
	Dec. 31, 2014
Product Warranties Disclosures [Abstract]
Changes in Company's product warranty reserve	The following table presents the changes in the Company’s product warranty reserve:
		Three months ended December 31,						Nine months ended December 31,
	(in thousands)	2014			2013			2014			2013
	Total product warranty reserve at the beginning of the	$	666		$	325		$	328		$	152
	period
	Warranty reserve assumed from business acquisitions	—			—			—			54
	Warranty expense to cost of revenue	64			73			474			343
	Utilization	(35		)	(41		)	(107		)	(192		)
	Total product warranty reserve at the end of the period	$	695		$	357		$	695		$	357

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	9 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Contractual Obligation, Fiscal Year Maturity Schedule [Table Text Block]	Future obligations and commitments as of December 31, 2014, consisted of the following:
		Payments due within
	(in thousands)	Year 1		Year 2		Year 3		Year 4		Year 5		Thereafter		Total
	Purchase obligations	$	5,865	$	—	$	—	$	—	$	—	$	—	$	5,865
	Future minimum operating lease	3,189		2,695		1,597		280		87		—		7,848
	payments
	Contingent consideration	727		811		—		—		—		—		1,538
	Future obligations and	$	9,781	$	3,506	$	1,597	$	280	$	87	$	—	$	15,251
	commitments

Shortterm_Investments_Tables

Short-term Investments (Tables)	9 Months Ended
	Dec. 31, 2014
Short-term Investments [Abstract]
Short-term investments	The following table presents short-term investments as of December 31, 2014, and March 31, 2014:
	(in thousands)	December 31, 2014		March 31, 2014
	Certificates of deposit	$	8,413	$	1,476
	Held-to-maturity, pre-refunded municipal bonds	16,809		14,108
	Total short-term investments	$	25,222	$	15,584

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	9 Months Ended
	Dec. 31, 2014
Fair Value Disclosures [Abstract]
Assets and liabilities measured at fair value on a recurring basis and their related valuation inputs	The following table presents financial assets and non-financial liabilities measured at fair value on a recurring basis and their related valuation inputs as of December 31, 2014:
	(in thousands)	Total Fair Value			Quoted Prices in			Significant Other	Significant		Balance Sheet
		of Asset or			Active Markets			Observable Inputs	Unobservable		Classification
		Liability			for Identical Assets			(Level 2)	Inputs
					(Level 1)				(Level 3)
	Assets:
	Money market funds	$	2,111		$	2,111		—	—		Cash and cash
											equivalents
	Liabilities:
	Contingent consideration, current	$	727		—			—	$	727	Contingent
											consideration
	Contingent consideration, non-	$	811		—			—	$	811	Contingent consideration non-current
	current
	The following table presents financial assets and liabilities measured at fair value on a recurring basis and their related valuation inputs as of March 31, 2014:
	(in thousands)	Total Fair Value			Quoted Prices in			Significant Other	Significant		Balance Sheet
		of Asset or			Active Markets			Observable Inputs	Unobservable		Classification
		Liability			for Identical Assets			(Level 2)	Inputs
					(Level 1)				(Level 3)
	Assets:
	Money market funds	$	117		$	117		—	—		Cash and cash
											equivalents
	Liabilities:
	Contingent consideration, current	$	2,067		—			—	$	2,067	Contingent consideration
	Contingent consideration, non-	$	574		—			—	$	574	Contingent
	current										consideration
											non-current
Fair value measurement of contingent consideration	The fair value measurement of contingent consideration as of December 31, 2014, and March 31, 2014, encompasses the following significant unobservable inputs:
	($ in thousands)	Unobservable Inputs
		31-Dec-14			31-Mar-14
	Estimated earn-out contingent consideration	$	3,500		$	3,500
	Working capital and other adjustment	(444		)	(444		)
	Indemnification related to warranty claims	(303		)	(303		)
	Discount rate	7.4		%	7.5		%
	Approximate timing of cash flows	1.6 years			1.4 years
Summarizes contingent consideration activity	The following table summarizes contingent consideration activity:
	(in thousands)
	Balance as of March 31, 2014	$	2,641
	Contingent consideration – payments	(1,104		)
	Contingent consideration – change in fair value in G&A expense	1
	Balance as of December 31, 2014	$	1,538

Basis_of_Presentation_Basis_of1

Basis of Presentation Basis of Presentation (Details) (USD $)	3 Months Ended			9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013		Dec. 31, 2014	Dec. 31, 2013
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue	$14,043	$25,236		$65,514	$77,652
Cost of revenue	9,648	13,304	[1]	43,370	45,281	[1]
Gross profit	4,395	11,932	[1]	22,144	32,371	[1]
Gross margin	31.30%	47.30%		33.80%	41.70%
Sales and marketing	2,719	3,205	[1]	9,064	9,749	[1]
Scenario, Previously Reported [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue		25,236			77,652
Cost of revenue		13,001			44,218
Gross profit		12,235			33,434
Gross margin		48.50%			43.10%
Sales and marketing		3,508			10,812
Restatement Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue		0			0
Cost of revenue		303			1,063
Gross profit		-303			-1,063
Sales and marketing		($303)			($1,063)
[1]	Certain amounts have been reclassified to reflect a change in accounting principle. See Note 1.

Basis_of_Presentation_Details_

Basis of Presentation (Details Textual) (USD $)	3 Months Ended			9 Months Ended
	Dec. 31, 2014	Dec. 31, 2013		Dec. 31, 2014	Dec. 31, 2013		Apr. 02, 2013	Mar. 02, 2014
Business Acquisition [Line Items]
Cost of revenue	$9,648,000	$13,304,000	[1]	$43,370,000	$45,281,000	[1]
CostofRevenueAdjustmentUsingPreviousAccountingGuidance	168,000			668,000
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income	0	0		0	0
Kentrox [Member]
Business Acquisition [Line Items]
Equity Method Investment, Ownership Percentage							100.00%
CSI [Member]
Business Acquisition [Line Items]
Equity Method Investment, Ownership Percentage								100.00%
Restatement Adjustment [Member]
Business Acquisition [Line Items]
Cost of revenue		$303,000			$1,063,000
[1]	Certain amounts have been reclassified to reflect a change in accounting principle. See Note 1.

Basis_of_Presentation_Basis_of2

Basis of Presentation Basis of Presentation (Details 1) (USD $)	3 Months Ended			9 Months Ended
	Dec. 31, 2014	Dec. 31, 2013		Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Sales and marketing	$2,719,000	$3,205,000	[1]	$9,064,000	$9,749,000	[1]
SalesandMarketingAdjustmentUsingPreviousAccountingGuidance	168,000			668,000
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Income from Continuing Operations	0	0		0	0
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets	0	0		0	0
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Diluted Earnings Per Share	$0	$0		$0	$0
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income	0	0		0	0
Restatement Adjustment [Member]
Business Acquisition [Line Items]
Sales and marketing		($303,000)			($1,063,000)
[1]	Certain amounts have been reclassified to reflect a change in accounting principle. See Note 1.

Acquistions_Details

Acquistions (Details) (USD $)	Dec. 31, 2014	Mar. 31, 2014		Sep. 30, 2014	Mar. 02, 2014
In Thousands, unless otherwise specified
Business Acquisition [Line Items]
Goodwill	$0	$31,102	[1]
IBW [Member]
Business Acquisition [Line Items]
Goodwill	0	0		20,547
CSI [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill					16,173
CSI [Member] | IBW [Member]
Business Acquisition [Line Items]
BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAcquired					6,513
Business Acquisition, Purchase Price Allocation, Current Assets Trade Accounts Receivable					2,900
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory					7,383
BusinessAcquisitionPurchasePriceAllocationCurrentAssetsOtherassets					135
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment					771
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill					16,173
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable					-2,912
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other					-1,175
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent					-6,293
Goodwill					20,547
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Less Noncontrolling Interest					44,042
CSI [Member] | Scenario, Previously Reported [Member]
Business Acquisition [Line Items]
BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAcquired					6,513
Business Acquisition, Purchase Price Allocation, Current Assets Trade Accounts Receivable					2,920
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory					7,625
BusinessAcquisitionPurchasePriceAllocationCurrentAssetsOtherassets					158
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment					816
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill					16,230
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable					-2,875
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other					-1,175
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent					-6,616
Goodwill					20,142
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Less Noncontrolling Interest					43,738
CSI [Member] | Restatement Adjustment [Member]
Business Acquisition [Line Items]
BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAcquired					0
Business Acquisition, Purchase Price Allocation, Current Assets Trade Accounts Receivable					-20	[2]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory					-242	[2]
BusinessAcquisitionPurchasePriceAllocationCurrentAssetsOtherassets					-23	[2]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment					-45	[2]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill					-57	[3]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable					-37	[2]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other					0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent					323	[3]
Goodwill					405
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Less Noncontrolling Interest					$304	[4]
[1]	Certain amounts have been adjusted to reflect measurement period adjustments related to the CSI acquisition.
[2]	Other measurement period adjustments mostly related to inventory adjustments
[3]	Intangible asset fair value adjustment for trade name and related tax effect
[4]	Payment for final working capital adjustment

Acquisitions_Details_2

Acquisitions (Details 2) (CSI [Member], USD $)	9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Mar. 02, 2014
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill		$16,173
Order or Production Backlog [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill		90
Finite-Lived Intangible Asset, Useful Life	0 years 1 month
Customer Relationships [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill		11,410
Finite-Lived Intangible Asset, Useful Life	9 years
Trademarks [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill		303
Finite-Lived Intangible Asset, Useful Life	1 year
Technology [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill		3,860
Finite-Lived Intangible Asset, Useful Life	3 years
Noncompete [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill		$510
Finite-Lived Intangible Asset, Useful Life	2 years

Acquisitions_Details_3

Acquisitions (Details 3) (USD $)	3 Months Ended	9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2013
Business Acquisition [Line Items]
Consolidated pro forma revenue	$35,312	$108,678
Consolidated pro forma operating loss	$2,498	$6,607

Acquisitions_Details_Textual

Acquisitions (Details Textual) (USD $)	3 Months Ended					9 Months Ended		12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Mar. 31, 2014		Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Mar. 31, 2014		Mar. 02, 2014
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired										100.00%
Business Acquisition, Cost of Acquired Entity, Cash Paid			$39,000,000
Working Capital Adjustment										5,000,000
Business Combination, Acquisition Related Costs						39,000		200,000
Revenue	14,043,000				25,236,000	65,514,000	77,652,000
Operating income (loss)	-27,583,000				2,023,000	-45,193,000	716,000
Goodwill	0		31,102,000	[1]		0		31,102,000	[1]
Goodwill impairment	20,547,000	10,555,000				31,102,000
CSI [Member]
Business Acquisition [Line Items]
Goodwill	0		20,547,000			0		20,547,000
CSI [Member]
Business Acquisition [Line Items]
Revenue	5,100,000					22,900,000
Operating income (loss)	$2,400,000					$3,300,000
[1]	Certain amounts have been adjusted to reflect measurement period adjustments related to the CSI acquisition.

Goodwill_and_Intangibles_Goodw2

Goodwill and Intangibles Goodwill and Intangibles (Details) (USD $)	3 Months Ended			9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Dec. 31, 2014	Mar. 31, 2014
Goodwill [Line Items]
Goodwill impairment	($20,547)	($10,555)		($31,102)
Goodwill	0			0	31,102	[1]
Goodwill, Transfers			0
Kentrox [Member]
Goodwill [Line Items]
Goodwill	0			0	10,555
Goodwill, Transfers			-10,555
CSI [Member]
Goodwill [Line Items]
Goodwill	0			0	20,547
Goodwill, Transfers			-20,547
CSG [Member]
Goodwill [Line Items]
Goodwill impairment		-10,555
Goodwill	0			0	0
Goodwill, Transfers			10,555
IBW [Member]
Goodwill [Line Items]
Goodwill impairment	-20,547
Goodwill	0	20,547		0	0
Goodwill, Transfers			$20,547
[1]	Certain amounts have been adjusted to reflect measurement period adjustments related to the CSI acquisition.

Goodwill_and_Intangibles_Goodw3

Goodwill and Intangibles Goodwill and Intangibles (Details Textual) (USD $)	3 Months Ended		9 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2014	Mar. 31, 2014		Sep. 01, 2014	Mar. 02, 2014
Goodwill [Line Items]
Goodwill	$0		$0	$31,102,000	[1]
Goodwill impairment	20,547,000	10,555,000	31,102,000
Impairment of Intangible Assets (Excluding Goodwill)	0	100,000
IBW [Member]
Goodwill [Line Items]
Goodwill	0	20,547,000	0	0
Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount						13.00%
Goodwill impairment	20,547,000
CSG [Member]
Goodwill [Line Items]
Goodwill	0		0	0
Goodwill impairment		10,555,000
CSI [Member] | IBW [Member]
Goodwill [Line Items]
Goodwill							$20,547,000
[1]	Certain amounts have been adjusted to reflect measurement period adjustments related to the CSI acquisition.

Restructuring_Charge_Details

Restructuring Charge (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Restructuring charges
Liability at beginning of period			$57
Charged	0	38	55	273
Employee Severance [Member]
Restructuring charges
Liability at beginning of period			57	6
Charged			55	273
Paid			-112	-202
Liability at end of period	$0	$77	$0	$77

Restructuring_Charge_Details_T

Restructuring Charge (Details Textual) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Mar. 31, 2014
Restructuring Charge (Textual) [Abstract]
Restructuring	$0	$38	$55	$273
Total Restructuring and Related Cost to date	390		390
Unpaid balance of restructuring charges					$57

Interim_Segment_Information_De

Interim Segment Information (Details) (USD $)	3 Months Ended				9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Dec. 31, 2013		Dec. 31, 2014	Dec. 31, 2013
Segment information
Revenue	$14,043		$25,236		$65,514	$77,652
Cost of revenue	9,648		13,304	[1]	43,370	45,281	[1]
Gross profit	4,395		11,932	[1]	22,144	32,371	[1]
Gross margin	31.30%		47.30%		33.80%	41.70%
Research and development	4,353		2,527		13,128	7,845
Segment profit (loss)	42		9,405		9,016	24,526
Operating expenses:
Sales and marketing	2,719		3,205	[1]	9,064	9,749	[1]
General and administrative	2,797		3,402		9,131	10,200
Intangible amortization	1,562		737		4,857	3,588
Restructuring	0		38		55	273
Goodwill impairment	20,547	10,555			31,102
Operating income (loss)	-27,583		2,023		-45,193	716
Other income (expense), net	-29		-31		16	-63
Income tax benefit (expense)	72		-38		170	-125
Net income (loss) from continuing operations	-27,540		1,954		-45,007	528
CSG [Member]
Segment information
Revenue	8,629		23,425		34,882	72,774
Cost of revenue	6,144		12,037		24,827	41,977
Gross profit	2,485		11,388		10,055	30,797
Gross margin	28.80%		48.60%		28.80%	42.30%
Research and development	2,011		2,347		6,488	7,292
Segment profit (loss)	474		9,041		3,567	23,505
Operating expenses:
Goodwill impairment		10,555
IBW [Member]
Segment information
Revenue	5,414		1,811		30,632	4,878
Cost of revenue	3,504		1,267		18,543	3,304
Gross profit	1,910		544		12,089	1,574
Gross margin	35.30%		30.00%		39.50%	32.30%
Research and development	2,342		180		6,640	553
Segment profit (loss)	-432		364		5,449	1,021
Operating expenses:
Goodwill impairment	$20,547
[1]	Certain amounts have been reclassified to reflect a change in accounting principle. See Note 1.

Interim_Segment_Information_In

Interim Segment Information Interim Segment Information (Details Textual)	9 Months Ended
	Dec. 31, 2014
	segments
Segment Reporting [Abstract]
Number of Reportable Segments	2

Inventories_Details

Inventories (Details) (USD $)	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Components of inventories
Raw materials	$7,518	$9,076
Finished goods and sub-assemblies	15,391	14,980
Total inventories	$22,909	$24,056	[1]
[1]	Certain amounts have been adjusted to reflect measurement period adjustments related to the CSI acquisition.

StockBased_Compensation_Detail

Stock-Based Compensation (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Stock-based compensation expense
Stock-based compensation expense	$514	$553	$1,628	$1,293
Income tax expense	0	0	0	0
Total stock-based compensation expense after taxes	$514	$553	$1,628	$1,293

StockBased_Compensation_Detail1

Stock-Based Compensation (Details 1) (Employee Stock Option [Member], USD $)	9 Months Ended		12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014		Mar. 31, 2014
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding on March 31, 2014	1,835,445
Granted	40,000
Exercised	-69,200
Forfeited	-212,500
Expired	-252,430
Outstanding on December 31, 2014	1,341,315		1,835,445
Weighted-Average Exercise Price Per Share, Outstanding on March 31, 2014	$2.02
Weighted-Average Exercise Price Per Share, Granted	$3.47
Weighted-Average Exercise Price Per Share, Exercised	$2.24
Weighted-Average Exercise Price Per Share, Forfeited	$2.59
Weighted-Average Exercise Price Per Share, Expired	$2.68
Weighted-Average Exercise Price Per Share, Outstanding on December 31, 2014	$1.84		$2.02
Weighted-Average Remaining Contractual Term (in years), Outstanding on March 31, 2014	3 years 2 months 12 days		3 years 8 months 19 days
Weighted-Average Remaining Contractual Term (in years), Outstanding on December 31, 2014	3 years 2 months 12 days		3 years 8 months 19 days
Aggregate Intrinsic Value, Outstanding on March 31, 2014	$3,110	[1]
Aggregate Intrinsic Value, Outstanding on December 31, 2014	$417	[1]	$3,110	[1]
[1]	The intrinsic value for the stock options is calculated based on the difference between the exercise price of the underlying awards and the average of the high and low Westell Technologies’ stock price as of the reporting date.

StockBased_Compensation_Detail2

Stock-Based Compensation (Details 2) (USD $)	9 Months Ended
	Dec. 31, 2014
Restricted Stock [Member]
Restricted stock activity
Non-vested as of March 31, 2014	407,500
Granted	100,000
Vested	-337,500
Forfeited	0
Non-vested as of December 31, 2014	170,000
Weighted-Average Grant Date Fair Value, Non-vested as of March 31, 2014	$1.94
Weighted-Average Grant Date Fair Value, Granted	$3.53
Weighted-Average Grant Date Fair Value, Vested	$1.89
Weighted-Average Grant Date Fair Value, Forfeited	$0
Weighted-Average Grant Date Fair Value, Non-vested as of December 31, 2014	$2.98
Restricted Stock Units (RSUs) [Member]
Restricted stock activity
Non-vested as of March 31, 2014	1,679,000
Granted	524,500
Vested	-387,500
Forfeited	-364,750
Non-vested as of December 31, 2014	1,451,250
Weighted-Average Grant Date Fair Value, Non-vested as of March 31, 2014	$3.09
Weighted-Average Grant Date Fair Value, Granted	$2.70
Weighted-Average Grant Date Fair Value, Vested	$2.67
Weighted-Average Grant Date Fair Value, Forfeited	$2.72
Weighted-Average Grant Date Fair Value, Non-vested as of December 31, 2014	$3.15
Performance Shares [Member]
Restricted stock activity
Non-vested as of March 31, 2014	285,000
Granted	217,500
Vested	-66,764
Forfeited	-102,431
Non-vested as of December 31, 2014	333,305
Weighted-Average Grant Date Fair Value, Non-vested as of March 31, 2014	$2.45
Weighted-Average Grant Date Fair Value, Granted	$3.83
Weighted-Average Grant Date Fair Value, Vested	$2.45
Weighted-Average Grant Date Fair Value, Forfeited	$3.04
Weighted-Average Grant Date Fair Value, Non-vested as of December 31, 2014	$3.16

StockBased_Compensation_Detail3

Stock-Based Compensation (Details Textual) (USD $)	3 Months Ended	9 Months Ended
	Dec. 31, 2014	Dec. 31, 2014
Stock-Based Compensation (Textual) [Abstract]
Vesting schedule of equal annual installments over four years		4 years
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value		$1.27
IncrementalStockbasedCompensationExpenseDuetoModification	$70,000	$158,000
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential PSU attainment range		0.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential PSU attainment range		200.00%

Product_Warranties_Details

Product Warranties (Details) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Changes in Company's product warranty reserve
Total product warranty reserve at the beginning of the period	$666	$325	$328	$152
Warranty reserve from business acquisitions				54
Warranty expense	64	73	474	343
Utilization	-35	-41	-107	-192
Total product warranty reserve at the end of the period	$695	$357	$695	$357

Product_Warranties_Details_Tex

Product Warranties (Details Textual) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Mar. 31, 2014
Product Warranties (Textual) [Abstract]
Current portions of warranty reserve	549	$286
Non-current portions of the warranty reserve	146	$42
CSG [Member] | Minimum [Member]
Product Warranties (Textual) [Abstract]
Standard Product Warranty Description	P1Y
CSG [Member] | Maximum [Member]
Product Warranties (Textual) [Abstract]
Standard Product Warranty Description	P7Y
IBW [Member] | Minimum [Member]
Product Warranties (Textual) [Abstract]
Standard Product Warranty Description	P1Y
IBW [Member] | Maximum [Member]
Product Warranties (Textual) [Abstract]
Standard Product Warranty Description	P5Y

Variable_Interest_Entity_and_G1

Variable Interest Entity and Guarantee (Details) (USD $)	3 Months Ended		9 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Mar. 31, 2014	Apr. 02, 2013
Concentration Risk [Line Items]
Revenue	$14,043,000	$25,236,000	$65,514,000	$77,652,000
AKA [Member]
Concentration Risk [Line Items]
Equity Method Investments	74,000		74,000		84,000
Revenue	300,000	1,300,000	1,400,000	3,900,000
Accounts Receivable, Net, Current	200,000		200,000		400,000
Deferred Revenue	1,100,000		1,100,000		1,000,000
Guarantor Obligations, Maximum Exposure, Undiscounted	$700,000		$700,000
AKA [Member]
Concentration Risk [Line Items]
Equity Method Investment, Ownership Percentage						50.00%

Income_Taxes_Details_Textual

Income Taxes (Details Textual) (USD $)	3 Months Ended		9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Income Taxes (Textual) [Abstract]
Income tax benefit (expense)	$72	($38)	$170	($125)
Effective tax rate	0.30%	1.90%	0.40%	19.10%

Commitments_and_Contingencies_1

Commitments and Contingencies (Details) (USD $)	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]
Purchase Obligation, Due in Next Twelve Months	$5,865
Purchase Obligation	5,865
Future minimum operating lease payments Due, Next Twelve Months	3,189
Future minimum operating lease payments, Due in Two Years	2,695
Future minimum operating lease payments, Due in Three Years	1,597
Future minimum operating lease payments, Due in Four Years	280
Future minimum operating lease payments, Due in Five Years	87
Future minimum operating lease payments Due	7,848
Contingent consideration, Due in Next Twelve Months	727
Contingent consideration, Due in Second Year	811
Contingent Consideration	1,538
Future obligations and commitments, Due in Next Twelve Months	9,781
Future obligations and commitments, Due in Second Year	3,506
Future obligations and commitments, Due in Third Year	1,597
Future obligations and commitments, Due in Fourth Year	280
Future obligations and commitments, Due in Fifth Year	87
Future obligations and commitments	$15,251	$23,700

Commitments_and_Contingencies_2

Commitments and Contingencies (Details Textual) (USD $)	9 Months Ended	12 Months Ended
	Dec. 31, 2014	Mar. 31, 2014
Loss Contingencies [Line Items]
Increase (decrease) in future obligations and commitments	$8,400,000
Future obligations and commitments	15,251,000	23,700,000
Payments for Previous Acquisition	1,104,000
Total contingent reserves related to intellectual property and indemnification claims	700,000	700,000
Maximum ANTONE earn-out that could be paid before offsets	3,500,000
Fair value of contingent consideration liability after offset of working capital adjustment and indemnification claim	1,538,000	2,641,000
Arkadin [Member]
Loss Contingencies [Line Items]
Escrow Deposit Released		$1,100,000

Commitments_and_Contingencies_3

Commitments and Contingencies Commitments and Contingencies (Details 1) (USD $)	Dec. 31, 2014	Mar. 31, 2014
In Millions, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]
Loss Contingency Accrual	$0.70	$0.70

Shortterm_Investments_Details

Short-term Investments (Details) (USD $)	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Schedule of Investments [Line Items]
Certificates of deposit	$8,413	$1,476
Held-to-maturity, pre-refunded municipal bonds	16,809	14,108
Total short-term investments	$25,222	$15,584

Fair_Value_Measurements_Detail

Fair Value Measurements (Details) (USD $)	Dec. 31, 2014	Mar. 31, 2014
In Thousands, unless otherwise specified
Assets and liabilities measured at fair value on a recurring basis and their related valuation inputs
Contingent consideration	$727	$2,067
Contingent consideration non-current	811	574
Recurring [Member] | Cash and cash equivalents [Member]
Assets and liabilities measured at fair value on a recurring basis and their related valuation inputs
Money market funds	2,111	117
Recurring [Member] | Accrued Liabilities [Member]
Assets and liabilities measured at fair value on a recurring basis and their related valuation inputs
Contingent consideration	727	2,067
Recurring [Member] | Contingent consideration non-current [Member]
Assets and liabilities measured at fair value on a recurring basis and their related valuation inputs
Contingent consideration non-current	811	574
Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Cash and cash equivalents [Member]
Assets and liabilities measured at fair value on a recurring basis and their related valuation inputs
Money market funds	2,111	117
Recurring [Member] | Unobservable Inputs (Level 3) [Member] | Accrued Liabilities [Member]
Assets and liabilities measured at fair value on a recurring basis and their related valuation inputs
Contingent consideration	727	2,067
Recurring [Member] | Unobservable Inputs (Level 3) [Member] | Contingent consideration non-current [Member]
Assets and liabilities measured at fair value on a recurring basis and their related valuation inputs
Contingent consideration non-current	$811	$574

Fair_Value_Measurements_Detail1

Fair Value Measurements (Details 1) (USD $)	9 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Mar. 31, 2014
Fair value measurement of contingent consideration
Maximum ANTONE earn-out that could be paid before offsets	$3,500
Unobservable Inputs (Level 3) [Member]
Fair value measurement of contingent consideration
Maximum ANTONE earn-out that could be paid before offsets	3,500	3,500
Working capital and other adjustment	-444	-444
Indemnification related to warranty claims	($303)	($303)
Discount rate	7.40%	7.50%
Approximate timing of cash flows	1 year 7 months 9 days	1 year 4 months 10 days

Fair_Value_Measurements_Detail2

Fair Value Measurements (Details 2) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014
Summarizes contingent consideration activity
Balance as of March 31, 2014	$2,641
Contingent consideration – payments	-1,104
Contingent consideration – change in fair value in G&A expense	1
Balance as of December 31, 2014	$1,538

Fair_Value_Measurements_Fair_V

Fair Value Measurements Fair Value Measurements (Details Textual) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Fair Value Disclosures [Abstract]
BusinessCombinationContingentConsiderationArrangementsRangeNetOfOutcomesValueLow	$1.10
BusinessCombinationContingentConsiderationArrangementsNetRangeOfOutcomesValueHigh	$2.70

Share_Repurchases_Details_Text

Share Repurchases (Details Textual) (Class A Common Stock, USD $)	9 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Aug. 31, 2011
August 2011 authorization [Member]
Share Repurchases (Textual) [Abstract]
Stock Repurchase Program			$20
Treasury Stock, Shares, Acquired	0	0
Stock Repurchase Program Remaining Authorized Repurchases Amount	$0.10
Outside of Publically Announced Repurchase Program [Member]
Share Repurchases (Textual) [Abstract]
Treasury Stock, Shares, Acquired	219,518	152,874
Treasury stock acquired volume weighted-average price	$3.16	2.08

Share_Repurchases_Share_Repurc

Share Repurchases Share Repurchases (Details) (August Two Thousand Eleven Authorization [Member], Class A Common Stock)	9 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
August Two Thousand Eleven Authorization [Member] | Class A Common Stock
Payments for Repurchase of Equity [Abstract]
Treasury Stock, Shares, Acquired	0	0

Subsequent_Event_Details

Subsequent Event (Details) (USD $)	3 Months Ended		9 Months Ended		3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Mar. 31, 2015
Subsequent Event [Line Items]
Restructuring	$0	$38	$55	$273
4Q15 Restructuring [Member]
Subsequent Event [Line Items]
Restructuring					$3,000