Inventories (Tables)

3 Months Ended

Mar. 31, 2015

Inventory Disclosure [Abstract]

Inventories

	March 31, 2015			December 31, 2014
	(in thousands)
Raw materials	$	39,384		$	34,153
Work in process	2,691			2,262
Finished goods	3,226			1,917
	45,301			38,332
Less:  Allowance for excess and obsolete inventories	(755		)	(714		)
Total, net	$	44,546		$	37,618

Inventories (Allowance)

The related changes in the allowance for excess and obsolete inventories account are as follows:

	Three months ended
	March 31, 2015		March 31, 2014
Allowance for excess and obsolete inventories:	(in thousands)
Balance, beginning of period	$	714	$	579
Provisions for excess and obsolete inventories	41		4
Inventories written off	—		—
Balance, end of period	$	755	$	583