Revenue (Tables)

12 Months Ended

Dec. 31, 2019

Revenue from Contract with Customer [Abstract]

Contract with Customer, Asset and Liability

The following table presents the beginning and ending balances of costs in excess of billings, billings in excess of cost and unearned revenue as of December 31, 2019 and 2018, respectively, and revenue recognized during the years ended December 31, 2019 and 2018, respectively, that was included in billings in excess of cost and unearned revenue at the beginning of the period, respectively (in thousands):

	December 31, 2019			December 31, 2018			January 1, 2018
Costs in excess of billings	$	20,607		$	22,634		$	16,532
Billings in excess of cost	(47,598		)	(17,857		)	(12,779		)
Unearned revenue	(17,311		)	(12,028		)	(3,336		)

	For the Year Ended December 31, 2019		For the Year Ended December 31, 2018
Revenue recognized in the period from:
Amounts included in billings in excess of cost  at the beginning of the period	$	17,371	$	10,097
Amounts included in unearned revenue  at the beginning of the period	$	11,092	$	2,988