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Represents the maximum additional number of shares that can be authorized under the share-based compensation arrangement to the extent that a corresponding number of equity awards previously granted under a prior plan expire or are cancelled or forfeited.

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No definition available.

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

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Sale Restriction Period

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vesting Percentage

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The number of shares that has been reserved for grants of options designated as incentive stock options under the plan.

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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.

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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

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No definition available.

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Unrecognized cost of unvested share-based compensation awards.

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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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The number of restricted shares issued as compensation, net of shares for the payment of withholding taxes. This element is to be used only if shares are used in lieu of cash to satisfy all or a portion of withholding taxes.

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No definition available.

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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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Intrinsic value of equity-based compensation awards not vested. Excludes stock and unit options.

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No definition available.

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

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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.

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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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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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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.

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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.

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

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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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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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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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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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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Stock-Based Compensation Plans and Employee Benefits (Stock-based Compensation) (Details) (USD $)	12 Months Ended			1 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 31, 2014	Feb. 28, 2013	Jan. 10, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 13,314,000	$ 19,261,000	$ 15,293,000
Unrecognized compensation cost	2,200,000
Weighted-average period to recognize the unrecognized compensation cost	1 year 5 months 1 day
Deferred compensation share-based arrangements, liability, current and noncurrent	8,700,000
2013 Performance Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Points Issued	83
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	39,200,000	31,600,000	29,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Shares, Non-vested at December 31, 2013	2,779,000			2,779,000
Granted, Number of Shares	306,000
Vested, Number of Shares	(2,757,000)
Forfeited, Number of Shares	(8,000)
Number of Shares, Non-vested at December 31, 2014	320,000	2,779,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted Average Grant Date Fair Value Per Share,Non-vested at December 31, 2013	$ 5.85			5.85
Granted, Weighted Average Grant Date Fair Value Per Share	$ 15.31
Vested, Weighted Average Grant Date Fair Value Per Share	$ 6.09
Forfeited, Weighted Average Grant Date Fair Value Per Share	$ 15.69
Weighted Average Grant Date Fair Value Per Share,Non-vested at December 31, 2014	$ 12.57	$ 5.85
Non-vested at December 31, 2013, Aggregate Intrinsic Value	39,659,000			39,659,000
Non-vested at December 31, 2014, Aggregate Intrinsic Value	4,367,000	39,659,000
Long-term Incentive Plan 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	8,000,000
Share-based Compensation Arrangement by Share-based Payment Award Additional Number of Shares that Can be Authorized	500,000
Long-term Incentive Plan 2006
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	4,550,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Reserved for Grants of Options	1,000,000
Long-term Incentive Plan 2006 and 2009
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance	4,000,000
Employees \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Vested, Number of Shares	(2,757,427)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Restricted shares awarded	1,369,809
Employees \| Amended restricted stock units vesting on January 1, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Vested, Number of Shares	(1,696,053)
Employees \| Service-based restricted stock units vesting on March 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Vested, Number of Shares	(80,000)
Employees \| Common Stock Subject to Sales Restriction
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Vested, Number of Shares				(235,414)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted Average Grant Date Fair Value Per Share,Non-vested at December 31, 2014	$ 14.89
Non-vested at December 31, 2014, Aggregate Intrinsic Value	$ 3,500,000
Restricted shares awarded	132,653
Employees \| Common Stock
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Sale restriction period				2 years
Employees \| Service-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Shares, Non-vested at December 31, 2014	64,552
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Granted units						67,637
Employees \| Performance-based restricted stock units vesting on December 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Shares, Non-vested at December 31, 2014	50,116
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Granted units						51,726
Risk-free interest rate				0.76%
Expected stock price volatility				44.84%
Employees \| Performance-based restricted stock units vesting on December 31, 2016 \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Vesting percentage				0.00%
Employees \| Performance-based restricted stock units vesting on December 31, 2016 \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Vesting percentage				200.00%
Employees \| Service-based restricted stock units vesting on February 1, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Shares, Non-vested at December 31, 2014	194,582
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Vesting term					3 years
Employees \| Performance based restricted stock units vesting on December 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Vested, Number of Shares	(381,374)
Employees \| Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Vesting percentage	195.50%
Employees \| Performance-based restricted stock units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Vesting percentage					0.00%
Employees \| Performance-based restricted stock units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Vesting percentage					200.00%
Employees \| Service based restricted stock units with specified vesting dates
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Shares, Non-vested at December 31, 2014	10,666
Employees \| Service based restricted stock units with specified vesting dates \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Vesting term	3 years
Company's chairman and chief executive officer \| Service-based restricted stock units vesting on June 15, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Vested, Number of Shares	(600,000)
Original Awards [Member] \| Employees \| Performance based restricted stock units vesting on December 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Vested, Number of Shares	(195,076)
Additional Awards [Member] \| Employees \| Performance based restricted stock units vesting on December 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Vested, Number of Shares	(186,298)