FAIR VALUE OF CERTAIN FINANCIAL ASSETS AND LIABILITIES (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Changes in fair value of Level 3 financial assets
Number of days for settlement basis, VRDNs to be liquidated at par	7
Minimum
Fair value of level 3 financial assets, roll forward
Investment Securities, Series Rate Setting Interval	7
Maximum
Fair value of level 3 financial assets, roll forward
Investment Securities, Series Rate Setting Interval	35
Auction rate securities
Fair value of level 3 financial assets, roll forward
Balance at the beginning of the period	$ 68,252	$ 84,325
Recognized gain (loss) included in income	(44)	(4,526)
Unrealized gain included in other comprehensive income	2,409	5,253
Settlements	(34,765)	(16,800)
Balance at the end of the period	35,852	68,252
Put options related to auction rate securities
Fair value of level 3 financial assets, roll forward
Balance at the beginning of the period	3,768
Recognized gain (loss) included in income	(727)	3,768
Balance at the end of the period	$ 3,041	$ 3,768

Represents the number of days in a rate setting predetermined intervals for auction rate securities.

No definition available.

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Period Type:	duration

- Definition

Represents the number of days for settlement basis, on which investment securities will be liquidated at par.

+ References

No definition available.

+ Details

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Namespace Prefix:	mnst_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Details

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- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

+ Details

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

- Definition

This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in other comprehensive income (a separate component of shareholders' equity).

+ References

+ Details

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

- Definition

Settlements that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant