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Significant Accounting Policies - Additional Information (Detail) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2020 USD ($) Facility State Segment | Oct. 29, 2020 USD ($)
Significant Accounting Policies [Line Items] |  |
Number of quarries and yards | Facility | 290 |
Number of states with aggregates business sales by destination | State | 27 |
Reportable business segments | Segment | 2 |
Restricted cash | $ 77.1 |
Number of days restricted from utilizing cash | 180 days |
Subsequent Event |  |
Significant Accounting Policies [Line Items] |  |
Restricted cash |  | $ 45.1

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- Definition Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=98513485&loc=SL98516268-108586 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(1)(a)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(2)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 + Details
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