Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities:
Net income	$ 2,436	$ 5,420
Adjustments to reconcile net income to cash (used in) provided by operating activities:
Depreciation and amortization	4,353	4,635
Provision for doubtful accounts	126	62
Stock-based compensation expense	2,016	739
Noncash operating lease expense	3,152	3,033
Amortization of debt issuance costs	251	1,620
Deferred income tax provision	391	211
Loss (gain) on sale of property and equipment	41	(18)
Loss on early debt extinguishment	1,961	0
(Gain) loss on change in fair value of warrant liability	(14)	1,312
Changes in operating assets and liabilities:
Accounts receivable	(12,678)	(19,834)
Contract assets	(5,095)	8,612
Other current assets	(1,243)	270
Accounts payable, including retainage	4,131	2,695
Prepaid income taxes	(217)	(192)
Accrued taxes payable	(1,426)	1,947
Contract liabilities	(9,645)	18,715
Operating lease liabilities	(3,036)	(3,229)
Accrued expenses and other current liabilities	(2,173)	8,925
Other long-term liabilities	(112)	306
Net cash (used in) provided by operating activities	(16,781)	35,229
Cash flows from investing activities:
Proceeds from sale of property and equipment	421	65
Advances to joint ventures	(2)	(3)
Purchase of property and equipment	(687)	(1,116)
Net cash used in investing activities	(268)	(1,054)
Cash flows from financing activities:
Proceeds from Wintrust Term Loan	30,000	0
Payments on Wintrust Term Loan	0	7,250
Payments on 2019 Revolving Credit Facility	0	(7,250)
Prepayment penalty and other costs associated with early debt extinguishment	(1,376)	0
Proceeds from the sale of common stock	22,773	0
Proceeds from the exercise of warrants	1,989	0
Payments on finance leases	(1,966)	(1,966)
Payments of debt issuance costs	(593)	0
Taxes paid related to net-share settlement of equity awards	(401)	(102)
Proceeds from contributions to Employee Stock Purchase Plan	278	149
Net cash provided by (used in) financing activities	8,204	(2,919)
(Decrease) increase in cash, cash equivalents and restricted cash	(8,845)	31,256
Cash, cash equivalents and restricted cash, beginning of period	42,260	8,457
Cash, cash equivalents and restricted cash, end of period	33,415	39,713
Noncash investing and financing transactions:
Right of use assets obtained in exchange for new operating lease liabilities	156	924
Right of use assets obtained in exchange for new finance lease liabilities	846	2,399
Right-of-use assets disposed or adjusted modifying operating leases liabilities	47	586
Right-of-use assets disposed or adjusted modifying finance leases liabilities	0	(64)
Interest paid	2,138	4,817
Cash paid (received) for income taxes	2,096	(629)
Wintrust Term Loan
Cash flows from financing activities:
Payments of Term Loans	(3,500)	0
2019 Refinancing Term Loan
Cash flows from financing activities:
Payments of Term Loans	$ (39,000)	$ (1,000)