Accrual for recall costs.

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- Definition

Contract Termination Fees

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No definition available.

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- Definition

Inventory on consignment

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No definition available.

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- Definition

Lease Expiration Month Year

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No definition available.

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- Definition

Lease Expiration Term

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No definition available.

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- Definition

Lease Liability

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No definition available.

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- Definition

Maturity of limited warranty.

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No definition available.

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- Definition

Number of major customers.

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No definition available.

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- Definition

Percentage of account receivables by customers.

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No definition available.

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- Definition

The interest rate for investments that have an interest rate. For fixed rate investments, this indicates the fixed interest rate. If the investment has a variable interest rate, the rate stated here may be the rate that is currently relevant. In this case the "Investment, Interest Rate is Current Rate for Variable Rate Investment Flag", "Investment, Interest Rate is Discount Rate at Purchase Flag", "Investment, Interest Rate Reflects Current Yield Flag" should be used. If one of these flags are not appropriate to explain the interest rate that is indicated, then a new flag should be added or an explanation should be included in "Investment, Additional Information".

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 12

-Sentence Column A

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The maturity date of the investment.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 12

-Sentence Column A

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable for incentive compensation awarded to employees and directors or earned by them based on the terms of one or more relevant arrangements. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Current Liabilities

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-SubTopic 10

-Section 45

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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- Definition

Aggregate carrying amount, as of the balance sheet date, of investments and other noncurrent assets not separately disclosed in the balance sheet due to materiality considerations. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

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No definition available.

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- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

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-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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- Definition

Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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-Name Accounting Standards Codification

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-Section 45

-Paragraph 28

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Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

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-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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Balance Sheet Information - Additional Information (Detail) (USD $)	3 Months Ended		1 Months Ended	12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Oct. 31, 2013	Dec. 31, 2014 Customer
Condensed Balance Sheet Statements, Captions [Line Items]
Percentage of account receivables by customers	10.00%			10.00%
Inventory held on consignment	$ 5,700,000htwr_InventoryOnConsignment			5,800,000htwr_InventoryOnConsignment
Impairment charge	1,118,000us-gaap_AssetImpairmentCharges	607,000us-gaap_AssetImpairmentCharges
Long-term investment, amount	14,341,000			14,635,000
Accrued payroll and other employee costs	2,400,000us-gaap_AccruedBonusesCurrent			7,900,000us-gaap_AccruedBonusesCurrent
Accrual for recall costs	505,000htwr_AccrualForRecallCosts	0htwr_AccrualForRecallCosts
Aggregate severance costs	600,000us-gaap_SeveranceCosts1
Contract termination fee	300,000htwr_ContractTerminationFees	700,000htwr_ContractTerminationFees
CircuLite [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Aggregate severance costs		600,000
Minimum [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Maturity of limited warranty	1 year
Maximum [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Maturity of limited warranty	2 years
Research and Development [Member] \| CircuLite [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Aggregate severance costs		400,000
Selling, General and Administrative [Member] \| CircuLite [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Aggregate severance costs		200,000
Facility Closing [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Lease liability	100,000
Lease expiration period	2017-10
Remaining lease payments	500,000	500,000
Lease expiration year		2020
Leasehold Improvements [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Impairment charge	1,100,000
Office Equipment And Software [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Impairment charge		600,000
Convertible Promissory Notes [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Long-term investment, amount			10,000,000
Long-term investment, interest rate			6.00%
Long-term investment, maturity date			Oct. 07, 2014
Preferred Stock Investment [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Long-term investment, amount	10,500,000			10,500,000
Allowance for Sales Returns [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Allowance for returns	$ 0			0
Accounts Receivable [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Number of customers having account receivable balance	0			0