Significant Accounting Policies (Detail) |
3 Months Ended | ||
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Apr. 23, 2018 |
Dec. 31, 2018 |
Dec. 31, 2017 |
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Class B Common Stock | |||
Concentration Risk [Line Items] | |||
Stock split, conversion ratio | 25.2 | ||
Revenues | Customer Concentration Risk | Department of Transportation | |||
Concentration Risk [Line Items] | |||
Concentration risk percentage | 37.30% | 37.30% | |
Revenues | Customer Concentration Risk | Alabama Department of Transportation | |||
Concentration Risk [Line Items] | |||
Concentration risk percentage | 9.60% | 13.20% | |
Revenues | Customer Concentration Risk | North Carolina Department of Transportation | |||
Concentration Risk [Line Items] | |||
Concentration risk percentage | 14.20% | 13.20% |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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