Minimum Average Share Price for Vesting

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- Definition

Number of Share-Based Compensation Plans

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- Definition

Percentage of Options That Vest if Minimum Trading Period Price is Reached

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options and Equity Instruments Other than Options, Outstanding, Number

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No definition available.

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- Definition

Vesting Period for Minimum Stock Price Average

+ 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.

+ References

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-Name Staff Accounting Bulletin (SAB)

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-Section F

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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- Definition

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

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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

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 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).

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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

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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- 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

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

+ References

No definition available.

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- Definition

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

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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Stock-Based Compensation - Narrative (Details) (USD $)	12 Months Ended
Stock-Based Compensation - Narrative (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense	$ 5,300,000	$ 6,300,000	$ 6,600,000
Number of stock-based compensation award plans	4imn_NumberOfShareBasedCompensationPlans
Options expiration term	10 years
Award vesting period	4 years
Number of stock-based compensation awards consisting of stock options and restricted stock outstanding	2,591,649
Aggregate intrinsic value (less than)	100,000	800,000	100,000
Intrinsic value of options exercised in period (less than)	100,000
Grants in period, weighted average grant date fair value (dollars per share)	$ 1.72	$ 1.61	$ 2.53
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense	1,400,000	2,700,000	3,300,000
Granted in period, shares	61,275	1,034,406	1,178,780
Aggregate intrinsic value (less than)	0	800,000	0	0
Tax benefit from stock-based compensation expense	500,000	900,000	1,100,000
Total unrecognized compensation expense related to non-vested stock	500,000
Total unrecognized compensation expense related to non-vested stock, period of recognition	1 year 1 month 6 days
Performance-based Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted in period, shares	61,275	113,125	0
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation expense	3,900,000	3,600,000	3,300,000
Tax benefit from stock-based compensation expense	1,500,000	1,500,000	1,400,000
Total unrecognized compensation expense related to non-vested stock	2,400,000
Total unrecognized compensation expense related to non-vested stock, period of recognition	1 year 6 months
Stock-based compensation capitalized	0	0	0
Deferred tax assets, recognized tax benefit	0	0	0
Total fair value of shares vested in period	$ 3,800,000	$ 3,900,000	$ 3,300,000
Number of shares granted	1,229,249	837,443	708,573
Performance-based Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted in period, shares	914,768	529,141	0
Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options expiration term	5 years
Number of shares granted	700,000.0	3,100,000.0
Stock Incentive Plan 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock-based compensation awards consisting of stock options and restricted stock outstanding	2,655,254
Number of shares authorized to award	6,000,000.0
Number of shares available for grant	1,929,545
Stock Incentive Plan 2011 \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options expiration term	10 years
Award vesting period	3 years
Share-based Compensation Award, Tranche One \| Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of options that vest if minimum trading period price is reached	50.00%
Vesting period for minimum stock price average	30 days
Minimum average share price for vesting	$ 10
Share-based Compensation Award, Tranche Two \| Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of options that vest if minimum trading period price is reached	50.00%
Vesting period for minimum stock price average	30 days
Minimum average share price for vesting	$ 15