Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Operating Loss Carryforwards [Line Items]
Current tax expense	$ 271	$ 22	$ 22
Deferred tax expense	913	141
Income tax expense	1,184	163
Cash paid for income taxes	44	0
Effective income tax reconciliation, decrease in valuation allowance		$ 203
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards			$ 83,270
Operating loss carryforward expiration period			18 years
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards			$ 44,857
Minimum | State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforward expiration period			8 years
Maximum | State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforward expiration period			18 years
Plateau Excavation
Operating Loss Carryforwards [Line Items]
Effective income tax reconciliation, state income taxes	$ 332