Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 16,648	$ 141,053
Accounts receivable, net	178,084	151,096
Inventories	100,872	83,753
Prepaid expenses and other assets	23,645	25,152
Total current assets	319,249	401,054
Property, plant and equipment, net	505,395	460,365
Operating lease assets	36,250	34,571
Goodwill and other intangible assets, net	18,791	19,001
Other assets	7,609	5,330
Total assets	887,294	920,321
Current liabilities:
Accounts payable	57,825	24,861
Accrued expenses and other liabilities	74,698	58,041
Accrued warranty	6,300	5,800
Total current liabilities	138,823	88,702
Deferred income taxes	43,967	43,967
Operating lease liabilities	29,239	28,263
Non-current accrued warranty	22,230	22,795
Other long-term liabilities	11,560	11,560
Total liabilities	245,819	195,287
Commitments and contingencies
Stockholders' equity:
Preferred stock, $0.01 par value, 3,000,000 shares authorized; none issued and outstanding	0	0
Common stock, $0.01 par value, 360,000,000 shares authorized; 140,798,762 and 140,734,753 shares issued and 111,563,381 and 115,148,152 shares outstanding at June 30, 2022 and December 31, 2021, respectively	1,408	1,407
Additional paid-in capital	129,109	127,787
Retained earnings	1,106,175	946,048
Treasury stock, at cost, 29,235,381 and 25,586,601 shares at June 30, 2022 and December 31, 2021, respectively	(595,217)	(350,208)
Total stockholders' equity	641,475	725,034
Total liabilities and stockholders' equity	$ 887,294	$ 920,321