Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Statement of Other Comprehensive Income [Abstract]
NET INCOME	$ 4,694	$ 9,212	$ 16,141	$ 28,998
Other comprehensive income:
Unrealized gains on investments	57	(91)	226	559
Income tax expense related to unrealized gains on investments	22	(35)	87	220
Other comprehensive income, net of tax	35	(56)	139	339
COMPREHENSIVE INCOME	4,729	9,156	16,280	29,337
Less: comprehensive income attributable to the noncontrolling interest	(9)	0	(13)	0
COMPREHENSIVE INCOME ATTRIBUTABLE TO MICREL, INCORPORATED SHAREHOLDERS	$ 4,720	$ 9,156	$ 16,267	$ 29,337

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References+ Details

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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- Definition

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References+ Details

- Definition

Before tax and reclassification adjustments amount of unrealized holding gain (loss) and transfers on available-for-sale securities.

+ References

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+ Details

- Definition

Tax effect of unrealized holding gain (loss) before reclassification adjustments and transfers on available-for-sale securities.

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- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

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