Other Investments - Additional Information (Detail)	9 Months Ended	12 Months Ended
	Sep. 30, 2015 USD ($)	Dec. 31, 2016 USD ($) Agreement	Dec. 31, 2014 USD ($)	Dec. 31, 2008 USD ($)
Variable Interest Entity [Line Items]
Preferred stock, redemption terms		Redemption was effected through the exchange of a share of preferred stock for (a) the right to receive the preference value in cash upon surrender of the preferred shares and (b) the non-transferable right to receive certain cash payments as additional consideration, after a period of 16 months, associated with (i) the release by Intersil of some or all of the $2,625,000 portion of total consideration held in escrow by Intersil for potential funding of indemnification and related obligations made by GWS and its selling shareholders and (ii) additional consideration of up to $4,000,000, payable in the event Intersil achieved certain revenue goals related to GWS products.
Maximum period to receive non-transferable right as cash		16 months
Consideration held in escrow		$ 2,625,000
Additional consideration payable		$ 4,000,000
Ownership interest in investment		27.00%
Great Wall Semiconductor Corporation (GWS) [Member]
Variable Interest Entity [Line Items]
Gross investment		$ 4,999,719		$ 0
Number of supply agreements with GWS | Agreement		2
Purchase of components under agreement	$ 1,662,000		$ 2,146,000