Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Jun. 30, 2021
Current assets:
Cash and cash equivalents (Note 1)	$ 65,040	$ 83,878
Restricted Cash, Current	2,600
Accounts receivable, less allowances (December 31, 2021—$547 and June 30, 2021—$898)	121,601	148,030
Costs and estimated earnings in excess of billings on uncompleted contracts	34,503	30,774
Inventories	6,297	7,342
Income taxes receivable	16,236	16,965
Other current assets	8,460	4,230
Total current assets	254,737	291,219
Property, plant and equipment at cost:
Land and buildings	41,545	41,633
Construction equipment	94,091	94,453
Transportation equipment	50,051	50,510
Office equipment and software	43,062	42,706
Construction in progress	282	493
Total property, plant and equipment - at cost	229,031	229,795
Accumulated depreciation	(166,296)	(160,388)
Property, plant and equipment - net	62,735	69,407
Restricted Cash, Noncurrent	25,000	0
Operating lease right-of-use assets	20,414	22,412
Goodwill	60,546	60,636
Other intangible assets, net of accumulated amortization	5,660	6,614
Deferred income taxes	0	5,295
Other assets, non-current	11,472	11,973
Total assets	440,564	467,556
Current liabilities:
Accounts payable	55,953	60,920
Billings on uncompleted contracts in excess of costs and estimated earnings	84,859	53,832
Accrued wages and benefits	15,968	21,008
Accrued insurance	6,175	6,568
Operating lease liabilities	5,364	5,747
Other accrued expenses	5,610	5,327
Total current liabilities	173,929	153,402
Deferred income taxes	33	34
Operating lease liabilities	18,925	20,771
Other liabilities, non-current	2,067	7,810
Total liabilities	194,954	182,017
Commitments and contingencies
Stockholders' equity:
Common stock—$.01 par value; 60,000,000 shares authorized; 27,888,217 shares issued as of December 31, 2021 and June 30, 2021; 26,773,975 and 26,549,438 shares outstanding as of December 31, 2021 and June 30, 2021	279	279
Additional paid-in capital	135,913	137,575
Retained earnings	132,721	175,178
Accumulated other comprehensive loss	(7,445)	(6,749)
Stockholders' equity	261,468	306,283
Less: Treasury stock, at cost — 1,114,242 shares as of December 31, 2021, and 1,338,779 shares as of June 30, 2021	(15,858)	(20,744)
Total stockholders' equity	245,610	285,539
Total liabilities and stockholders’ equity	$ 440,564	$ 467,556