Defined Benefit Pension Plan	12 Months Ended
Defined Benefit Pension Plan	Dec. 27, 2014
Compensation and Retirement Disclosure [Abstract]
Defined Benefit Pension Plan	Defined Benefit Pension Plan Nanometrics sponsors a statutory government mandated defined benefit pension plan (the “Benefit Plan”) in Taiwan for its local employees. The fair value of plan assets was $0.2 million, $0.2 million and $0.2 million for the fiscal years ended 2014, 2013 and 2012, respectively; and the net funding deficiency of the Benefit Plan was $0.3 million, $0.2 million, and $0.3 million for the fiscal years ended December 27, 2014, December 28, 2013, and December 29, 2012, respectively. Based on the nature and limited extent of the pension plan, we determined this pension plan was not material for separate disclosure.

The entire disclosure for pension and other postretirement benefits.