Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
NET INCOME	$ 13,547us-gaap_ProfitLoss	$ 17,648us-gaap_ProfitLoss	$ 12,328us-gaap_ProfitLoss
Other comprehensive income:
Unrealized gains on investments	366	303	608
Reclassification adjustment for a realized loss on investment included in other expense	0	26	0
Income tax provision	(129)	(117)	(253)
Other comprehensive income, net of taxes	237	212	355
COMPREHENSIVE INCOME	13,784	17,860	12,683
Less: comprehensive income attributable to noncontrolling interest	0	0	(10)
COMPREHENSIVE INCOME ATTRIBUTABLE TO MICREL, INCORPORATED SHAREHOLDERS	$ 13,784us-gaap_ComprehensiveIncomeNetOfTax	$ 17,860us-gaap_ComprehensiveIncomeNetOfTax	$ 12,673us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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