The purchase price per share paid to shareholders of acquired entity.

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- Definition

Conversion ratio

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- Definition

Converted RailAmerica restricted stock units

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- Definition

Equity awards conversion price for RailAmerica converted shares

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- Definition

RailAmerica converted restricted stock awards

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- Definition

RailAmerica restricted stock awards before conversion

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- Definition

RailAmerica restricted stock units before conversion

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Number

+ References

No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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- Definition

The number of grants made 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).

+ References

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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).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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-Subparagraph (c)(2)(iii)(1)

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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

-Publisher FASB

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-SubTopic 10

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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- Definition

The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

+ References

No definition available.

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Stock-Based Compensation Restricted Stock Units (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended		12 Months Ended
	Dec. 31, 2012	Oct. 02, 2012	Dec. 31, 2012 Restricted Stock Units (RSUs) [Member]	Dec. 31, 2011 Restricted Stock Units (RSUs) [Member]	Dec. 31, 2010 Restricted Stock Units (RSUs) [Member]	Oct. 02, 2012 RailAmerica [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
RailAmerica restricted stock awards before conversion		432,000
RailAmerica restricted stock units before conversion		775,000
RailAmerica converted restricted stock awards		180,000
RailAmerica converted restricted stock units		322,000
Conversion ratio		0.4151
Equity awards conversion price for RailAmerica converted shares		$ 66.26
Acquisition Purchase Price Per Share						$ 27.50
Restricted Stock Units [Abstract]
Non-vested at beginning of year			15,916
Granted			335,583
Vested			53,148
Forfeited			3,716
Non-vested at end of year			294,635	15,916
Weighted Average Grant Date Fair Value [Abstract]
Non-vested at beginning of year			$ 47.08
Granted	$ 61.11		$ 67.43
Vested			$ 64.41
Forfeited			$ 67.75
Non-vested at end of year			$ 66.86	$ 47.08
Weighted average grant date fair value of restricted stock granted during the year			$ 67.43	$ 56.17	$ 35.96
Total intrinsic value of restricted stock that vested during year			$ 3.4	$ 0.3	$ 0.1