Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Mar. 31, 2015
Inventory [Line Items]
Raw materials	$ 15,135	$ 13,263
Work in process	248,277	197,565
Finished goods	100,348	68,628
Inventory, Net	363,760	$ 279,456
Micrel Incorporated [Member]
Inventory [Line Items]
Acquired inventory fair value adjustment, remaining balance	$ 37,200

The amount remaining of the acquired inventory fair value adjustment resulting from a business combination.

No definition available.

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- Definition

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

+ References

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-Publisher FASB

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- 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.

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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

+ References

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-Publisher FASB

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- Definition

Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

+ References

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-Publisher FASB

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