Contingencies (Detail) - Warranty Liability (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Change in Warranty Liability
Aggregate product warranty liability at beginning of period	$ 268us-gaap_ProductWarrantyAccrual	$ 596us-gaap_ProductWarrantyAccrual
Net aggregate expense (benefit) related to product warranties	2us-gaap_ProductWarrantyExpense	(50)us-gaap_ProductWarrantyExpense
Aggregate reductions for payments	(2)us-gaap_ProductWarrantyAccrualPayments	(14)us-gaap_ProductWarrantyAccrualPayments
Aggregate product warranty liability at end of period	$ 268us-gaap_ProductWarrantyAccrual	$ 532us-gaap_ProductWarrantyAccrual

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.15(5))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph ((c)(5))

-URI http://asc.fasb.org/extlink&oid=51674963&loc=d3e12565-110249

+ Details

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Period Type:	instant

- Definition

Represents the aggregate decrease in the liability related to payments to satisfy claims for standard and extended product warranties.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph ((c)(2))

-URI http://asc.fasb.org/extlink&oid=51674963&loc=d3e12565-110249

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services granted to customers.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph ((c)(3,4))

-URI http://asc.fasb.org/extlink&oid=51674963&loc=d3e12565-110249

+ Details

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Balance Type:	debit
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