Revenue (Tables)

9 Months Ended

Sep. 30, 2019

Revenue from Contract with Customer [Abstract]

Revenue from External Customers by Geographic Areas

The following table summarizes net sales by end market:

(in thousands)	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
End Market	2019		2018		2019		2018
Energy	$	64,331	$	48,481	$	162,224	$	139,062
Industrial	37,020		52,367		142,267		146,137
Transportation	37,161		35,470		88,492		72,605
Total	$	138,512	$	136,318	$	392,983	$	357,804

The following table summarizes net sales by geographic area:

(in thousands)	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
Geographic Area	2019		2018		2019		2018
North America	$	125,971	$	120,955	$	343,593	$	312,346
Pacific Rim	6,744		10,913		30,173		32,768
Europe	4,329		3,012		12,712		9,948
Other	1,468		1,438		6,505		2,742
Total	$	138,512	$	136,318	$	392,983	$	357,804

Schedule of Contract Balances

(in thousands)	As of
	September 30, 2019			December 31, 2018
Short-term contract assets (included in Prepaid expenses and other current assets)	$	4,038		$	2,926
Short-term contract liabilities (included in Other accrued liabilities)	(15,959		)	(4,897		)
Long-term contract liabilities (included in Noncurrent contract liabilities)	(12,622		)	(14,611		)
Net contract liabilities	$	(24,543	)	$	(16,582	)