CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Current assets:
Cash and cash equivalents	$ 489,417	$ 687,192
Short-term marketable securities	105,895	102,634
Accounts receivable, net of allowances aggregating $48,888 and $47,242, respectively	1,077,510	1,015,357
Unbilled accounts receivable	171,089	162,215
Inventories and supplies	376,024	384,657
Prepaid expenses and other current assets	90,747	81,741
Total current assets	2,310,682	2,433,796
Property, plant and equipment, net	2,463,620	2,447,941
Other assets:
Operating lease right-of-use assets	247,414	250,853
Goodwill	1,477,307	1,477,199
Permits and other intangibles, net	688,957	701,987
Other long-term assets	58,407	65,502
Total other assets	2,472,085	2,495,541
Total assets	7,246,387	7,377,278
Current liabilities:
Current portion of long-term debt	15,102	15,102
Accounts payable	443,654	487,286
Deferred revenue	96,171	88,545
Accrued expenses and other current liabilities	325,759	419,445
Current portion of closure, post-closure and remedial liabilities	23,792	20,625
Current portion of operating lease liabilities	71,865	71,663
Total current liabilities	976,343	1,102,666
Other liabilities:
Closure and post-closure liabilities, less current portion of $12,948 and $10,304, respectively	121,221	119,484
Remedial liabilities, less current portion of $10,844 and $10,321, respectively	89,031	101,424
Long-term debt, less current portion	2,768,815	2,771,117
Operating lease liabilities, less current portion	179,454	182,883
Deferred tax liabilities	360,404	363,623
Other long-term liabilities	179,895	162,552
Total other liabilities	3,698,820	3,701,083
Commitments and contingent liabilities (See Note 15)
Stockholders’ equity:
Authorized 80,000,000 shares; issued and outstanding 53,636,038 and 53,832,692 shares, respectively	536	538
Additional paid-in capital	365,698	421,749
Accumulated other comprehensive loss	(218,567)	(213,635)
Retained earnings	2,423,557	2,364,877
Total stockholders’ equity	2,571,224	2,573,529
Total liabilities and stockholders’ equity	$ 7,246,387	$ 7,377,278