Arcosa Shares Received in Spin-Off

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- Definition

Share-based Compensation Arrangements by Share-based Payment Award, Allowance for Adjustment of Units Based on Target Level, Percent

+ References

No definition available.

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- Definition

Trinity Shares Converted in Spin-Off

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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.

+ References

No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Nov. 01, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock provided for awarding by the Plan (in shares)	20,150,000
Number of shares available for issuance (in shares)	3,520,541
Contractual term of award		10 years
Award vesting period	5 years
Trinity Shares Converted in Spin-Off				3
Arcosa Shares Received in Spin-Off				1
Stock-based compensation expense	$ 29,300,000	$ 24,600,000	$ 30,900,000
Income tax benefit related to stock-based compensation expense	7,700,000	14,500,000	14,500,000
Unrecognized compensation expense	0
Intrinsic value of options exercised	$ 700,000	$ 500,000	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	0	34,343
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term of award	10 years
Award vesting period	5 years
Restricted share awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to restricted share awards	$ 52,400,000
Weighted average recognition period	3 years 7 months
Vesting-date fair value of shares vested and released	$ 30,100,000	$ 50,200,000	$ 47,000,000
Weighted average grant-date fair value of restricted share awards granted (in dollars per share)	$ 35.02	$ 28.87	$ 19.06
Restricted stock \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	1 year
Restricted stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	15 years
Performance units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Performance units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target grant potentially issuable depending on achievement of certain specified goals	0.00%
Performance units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target grant potentially issuable depending on achievement of certain specified goals	200.00%