Accounting Policies (Policies)	3 Months Ended
Accounting Policies (Policies)	Dec. 31, 2025
Accounting Policies [Abstract]
Use of Estimates, Policy	Use of Estimates The preparation of financial statements in conformity with GAAP requires the use of estimates and assumptions by management in determining the reported amounts of assets and liabilities, disclosures of contingent liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Estimates are primarily used in our revenue recognition of construction in progress, fair value assumptions in accounting for business combinations, stock-based compensation, reserves for legal matters, and realizability of deferred tax assets and unrecognized tax benefits.
Equity Method Investments	Equity Method Investments We account for investments using the equity method of accounting if the investment gives us the ability to exercise significant influence over an investee but does not grant us control. Significant influence generally exists when an investor owns 20% or more of the voting stock of an incorporated investee or a more than 3% to 5% interest in an unincorporated investee. Under the equity method of accounting, the carrying amount of an investment is initially recorded at cost basis and is subsequently adjusted for our proportionate share of earnings or losses, additional investments in the entity, and distributions. Our proportionate share of earnings or losses is recorded in Equity method investment income on our Condensed Consolidated Statements of Comprehensive Income.

Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478671/942-235-S50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 235
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(b)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477314/942-235-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-12

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-9

Reference 5: http://www.xbrl.org/2003/role/exampleRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482836/275-10-55-6

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-6

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-4

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-SubTopic 10
-Topic 275
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-SubTopic 10
-Topic 275
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-1

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