INTANGIBLE ASSETS: (Gross, Accumulated Amortization, Net) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross carrying value of amortizable intangible assets	$ 383,835		$ 390,802
Accumulated amortization	(116,460)		(112,771)
Net carrying value of amortizable intangible assets	267,375		278,031
Amortization of intangible assets	15,000	$ 11,700
Licensed technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying value of amortizable intangible assets	28,916		24,583
Accumulated amortization	(8,732)		(6,559)
Net carrying value of amortizable intangible assets	20,184		18,024
Developed technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying value of amortizable intangible assets	250,043		250,043
Accumulated amortization	(86,178)		(75,591)
Net carrying value of amortizable intangible assets	163,865		174,452
Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying value of amortizable intangible assets	69,776		69,776
Accumulated amortization	(19,494)		(17,731)
Net carrying value of amortizable intangible assets	50,282		52,045
Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying value of amortizable intangible assets			11,300
Accumulated amortization			(11,300)
Net carrying value of amortizable intangible assets			0
Trade names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying value of amortizable intangible assets	5,600		5,600
Accumulated amortization	(2,056)		(1,590)
Net carrying value of amortizable intangible assets	3,544		4,010
Finite lived amortizable intangible assets [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying value of amortizable intangible assets	354,335		361,302
Accumulated amortization	(116,460)		(112,771)
Net carrying value of amortizable intangible assets	237,875		248,531
In Process research and development [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying value of amortizable intangible assets	29,500		29,500
Accumulated amortization	0		0
Net carrying value of amortizable intangible assets	$ 29,500		$ 29,500

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

+ Details

Name:	us-gaap_AmortizationOfIntangibleAssets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetsGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

Name:	us-gaap_FiniteLivedIntangibleAssetsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_LicensingAgreementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_DevelopedTechnologyRightsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_CustomerRelationshipsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_OrderOrProductionBacklogMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_TradeNamesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=mlnx_FiniteLivedIntangibleAssetsExcludingInProcessResearchAndDevelopmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_InProcessResearchAndDevelopmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: