Revenue (Tables)

6 Months Ended

Jun. 30, 2020

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 June 30,				For the Six Months Ended June 30,
End Market	2020		2019		2020		2019
Energy	$	29,649	$	52,245	$	79,733	$	97,893
Industrial	30,463		54,660		67,594		105,247
Transportation	32,944		31,779		50,826		51,331
Total	$	93,056	$	138,684	$	198,153	$	254,471

The following table summarizes net sales by geographic area:

(in thousands)	For the Three Months Ended June 30,				For the Six Months Ended June 30,
Geographic Area	2020		2019		2020		2019
North America	$	81,979	$	119,943	$	176,499	$	217,622
Pacific Rim	6,295		10,804		12,749		23,429
Europe	2,578		5,006		5,235		8,383
Other	2,204		2,931		3,670		5,037
Total	$	93,056	$	138,684	$	198,153	$	254,471

Schedule of Contract Balances

(in thousands)	As of June 30, 2020			As of December 31, 2019
Short-term contract assets (included in Prepaid expenses and other current assets)	$	2,340		$	694
Short-term contract liabilities (included in Other accrued liabilities)	(52,412		)	(26,898		)
Long-term contract liabilities (included in Noncurrent contract liabilities)	(3,062		)	(17,998		)
Net contract liabilities	$	(53,134	)	$	(44,202	)