Compensation related to the settlement of accelerated equity awards in the form of cash.

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Compensation related to the settlement of accelerated equity awards in the form of Company stock or Cash.

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Share based compensation related to the settlement of accelerated equity awards in the form of Company stock.

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No definition available.

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Represents the high end of the range of the weighted average period between the balance sheet date and the expiration for all awards outstanding under the plan, which may be expressed in a decimal value for the number of years in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Represents the low end of the range of the weighted average period between the balance sheet date and the expiration for all awards outstanding under the plan, which may be expressed in a decimal value for the number of years in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The period of time over which the employee needs to meet the performance objectives in order to qualify for the stock unit award in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices pertaining to all outstanding stock options which are in the customized range of exercise prices as of the balance sheet date.

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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-Name Staff Accounting Bulletin (SAB)

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Unrecognized cost of unvested share-based compensation awards.

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- Definition

Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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-Topic 718

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-Section 55

-Paragraph 24

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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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-Paragraph 2

-Subparagraph (a)(1)

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No definition available.

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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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-Publisher FASB

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- Definition

Gross number of share options (or share units) granted during the period.

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No definition available.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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-Name Accounting Standards Codification

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- Definition

Weighted average remaining contractual term of exercisable stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock Plans (Details 2) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Compensation expense
Recognized compensation expense	$ 112,200	$ 34,400	$ 32,600
Unrecognized compensation expense	$ 115,500
Vesting period	3 years
Excess tax benefit from share-based payment	$ 3,642	748	1,754
URS Corporation \| Acquisition And Integration Expenses
Compensation expense
Compensation to settle accelerated equity awards	43,900
Accelerated equity award - Company stock	17,600
Accelerated equity award - cash	$ 26,300
Employee Stock Option
Options Outstanding
Number outstanding as of end of period (in shares)	1,300,000
Weighted Average Remaining Contractual Life	4 years 8 months 9 days
Weighted Average Exercise Price (in dollars per share)	$ 28.26
Aggregate Intrinsic Value (in millions)	$ 2,000
Options Exercisable
Number Exercisable at the end of the period (in shares)	700,000
Weighted Average Remaining Contractual Life	1 year 1 month 6 days
Weighted Average Exercise Price (in dollars per share)	$ 25.04
Stock Incentive Plans, additional disclosures
Remaining contractual life of options outstanding, low end of range	15 days
Remaining contractual life of options outstanding, high end of range	8 years 5 months 5 days
Aggregate intrinsic value of stock options exercised	$ 2,100	$ 4,300	7,900
Compensation expense
Weighted average grant-date fair value of stock options granted (in dollars per share)		$ 7.83
Number of stock options granted during the period	0
Excess tax benefit from share-based payment	$ 3,600	$ 700	$ 1,800
Performance Earnings Program
Compensation expense
Weighted average grant-date fair value of stock options granted (in dollars per share)	$ 32.32	$ 29.32	$ 22.27
Performance period over which objectives must be met to qualify for an award grant	3 years
Restricted Stock Units (RSUs)
Compensation expense
Weighted average grant-date fair value of stock options granted (in dollars per share)	$ 31.05	$ 29.60	$ 22.83
Restricted Stock Units (RSUs) \| URS Corporation
Compensation expense
Weighted average grant-date fair value of stock options granted (in dollars per share)	$ 30.04
Number of stock options granted during the period	2,600,000
Exercise Price Range from Dollars 21.01 to Dollars 23.94
Information concerning outstanding and exercisable options
Exercise price, low end of range (in dollars per share)	$ 21.01
Exercise price, high end of range (in dollars per share)	$ 23.94
Exercise Price Range from Dollars 21.01 to Dollars 23.94 \| Employee Stock Option
Options Outstanding
Number outstanding as of end of period (in shares)	200,000
Weighted Average Remaining Contractual Life	2 months 23 days
Weighted Average Exercise Price (in dollars per share)	$ 23.19
Aggregate Intrinsic Value (in millions)	$ 1,100
Options Exercisable
Number Exercisable at the end of the period (in shares)	200,000
Weighted Average Remaining Contractual Life	2 months 23 days
Weighted Average Exercise Price (in dollars per share)	$ 23.19
Exercise Price Range From Dollars 24.45 To Dollars 27.67
Information concerning outstanding and exercisable options
Exercise price, low end of range (in dollars per share)	24.45
Exercise price, high end of range (in dollars per share)	$ 27.67
Exercise Price Range From Dollars 24.45 To Dollars 27.67 \| Employee Stock Option
Options Outstanding
Number outstanding as of end of period (in shares)	400,000
Weighted Average Remaining Contractual Life	1 year 5 months 19 days
Weighted Average Exercise Price (in dollars per share)	$ 25.43
Aggregate Intrinsic Value (in millions)	$ 900
Options Exercisable
Number Exercisable at the end of the period (in shares)	400,000
Weighted Average Remaining Contractual Life	1 year 5 months 19 days
Weighted Average Exercise Price (in dollars per share)	$ 25.43
Exercise Price Range From Dollars 28.04 To Dollars 31.62
Information concerning outstanding and exercisable options
Exercise price, low end of range (in dollars per share)	28.04
Exercise price, high end of range (in dollars per share)	$ 31.62
Exercise Price Range From Dollars 28.04 To Dollars 31.62 \| Employee Stock Option
Options Outstanding
Number outstanding as of end of period (in shares)	700,000
Weighted Average Remaining Contractual Life	7 years 8 months 1 day
Weighted Average Exercise Price (in dollars per share)	$ 31.25
Options Exercisable
Number Exercisable at the end of the period (in shares)	100,000
Weighted Average Remaining Contractual Life	2 years 4 days
Weighted Average Exercise Price (in dollars per share)	$ 28.53