CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities:
Net income	$ 18,118	$ 8,154
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	10,516	9,514
Amortization of deferred loan costs	359	293
Stock-based compensation	1,160	1,280
Stock Based Compensation - Restricted Stock	50
Provision for bad debts	32	39
Loss on disposition of assets	(25)
Non-cash operating lease expense	(1)	(4)
Deferred income taxes		1
Changes in operating assets and liabilities:
Receivables	1,362	(4,025)
Income taxes receivable	2,581	1,511
Inventories	187	855
Prepaid expenses	521	1,071
Accounts payable	835	703
Accrued expenses	(257)	2,462
Net cash provided by operating activities	35,438	21,854
Cash flows from investing activities:
Proceeds from sale of assets	27
Change in construction accounts payable	(7,266)	497
Acquisition of property and equipment	(14,814)	(6,427)
Net cash used in investing activities	(22,053)	(5,930)
Cash flows from financing activities:
Payroll taxes from net exercise of stock options	(2,468)
Proceeds from exercise of stock options	5,206	2,409
Long-term debt borrowings	3,000
Principal payments on long-term debt	(13,000)	(22,500)
Loan issuance cost	(6,500)
Net cash (used in) provided by financing activities	(13,762)	(20,091)
Change in cash and cash equivalents	(377)	(4,167)
Cash and cash equivalents at beginning of period	33,526	28,310
Cash and cash equivalents at end of period	33,149	24,143
Supplemental disclosure of cash flow information:
Cash paid for interest, net of amounts capitalized	$ 293	$ 1,328