Subsequent Event (Notes)	3 Months Ended
Subsequent Event (Notes)	Jun. 30, 2012
Notes to Financial Statements [Abstract]
Subsequent Events	Subsequent Event Completion of Acquisition of Standard Microsystems Corporation ("SMSC") On August 2, 2012, the Company closed its previously announced acquisition of SMSC pursuant to the Agreement and Plan of Merger dated as of May 1, 2012. As a result of the acquisition, SMSC became a wholly owned subsidiary of Microchip. Upon the closing of the acquisition, each share of common stock of SMSC was cancelled and automatically converted into the right to receive $37.00 in cash, without interest and less any applicable withholding taxes. The Company financed the transaction using approximately $258.8 million of its existing balance of cash, cash equivalents and short-term investments and borrowings of approximately $600.0 million under its existing credit agreement. At June 30, 2012, SMSC had approximately $193.4 million of cash and investments on its balance sheet. SMSC is a leading developer of Smart Mixed-Signal Connectivity™ solutions. SMSC employs a unique systems level approach that incorporates a broad set of technologies and intellectual property to deliver differentiating products to its customers. SMSC is focused on delivering connectivity solutions that enable the proliferation of data in automobiles, consumer devices, PCs and other applications. SMSC's feature-rich products drive a number of industry standards and include USB, MOST® automotive networking, Kleer® and JukeBlox® wireless audio, embedded system control and analog solutions, including thermal management and RightTouch® capacitive sensing. SMSC is headquartered in New York and has offices and research facilities in North America, Asia and Europe. Due to the fact that the SMSC acquisition just recently closed on August 2, 2012, it is not practical for the Company to file the required pro-forma financial information at this time. The Company will file such pro-forma financial information by an amendment to its Form 8-K (filed on August 2, 2012) not later than seventy-one (71) calendar days after the date that such Form 8-K was required to be filed.

Tabular disclosure of significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, losses resulting from fire or flood, losses on receivables, significant realized and unrealized gains and losses that result from changes in quoted market prices of securities, declines in market prices of inventory, changes in authorized or issued debt (SEC), significant foreign exchange rate changes, substantial loans to insiders or affiliates, significant long-term investments, and substantial dividends not in the ordinary course of business.

+ References+ Details