Segment Information - Additional Information (Detail) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2017 USD ($) Segment	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | Segment		3
Acquisition related costs		$ 344	$ 0	$ 11,682
Amortization of backlog intangibles		23,460	$ 25,998
NN Life Sciences Vandalia LLC [Member]
Segment Reporting Information [Line Items]
Acquisition related costs	$ 200	300
Business combinations revenue during period from acquired business		6,700
Business combinations net income (loss) during period from acquired business		(500)
Increase in cost of sales for inventory step-up		900
Precision Engineered Products Group [Member]
Segment Reporting Information [Line Items]
Business combinations revenue during period from acquired business				40,700
Business combinations net income (loss) during period from acquired business				(5,100)
Increase in cost of sales for inventory step-up				4,300
Amortization of backlog intangibles				5,200
Corporate and Consolidations [Member] | NN Life Sciences Vandalia LLC [Member]
Segment Reporting Information [Line Items]
Acquisition related costs		$ 300
Corporate and Consolidations [Member] | Precision Engineered Products Group [Member]
Segment Reporting Information [Line Items]
Non-recurring costs related to acquisition				$ 10,900