Stockholders' Equity - Restricted Stock Units (Details) $ / shares in Units, shares in Thousands, $ in Millions	6 Months Ended	35 Months Ended
Sep. 30, 2016 USD ($) $ / shares shares	Sep. 30, 2016 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Common stock, closing price per share (USD per share)	$ 6.95	$ 6.95
Outstanding RSUs
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of Shares, Beginning balance (in shares) \| shares	4,704
Number of Shares, Awarded (in shares) \| shares	1,940
Number of Shares, Vested (in shares) \| shares	(1,651)
Number of Shares, Cancelled (in shares) \| shares	(282)
Number of Shares, Ending balance (in shares) \| shares	4,711	4,711
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted Average Grant Date Fair Value, Beginning Balance (in Dollars per share)	$ 6.59
Weighted Average Grant Date Fair Value, Awarded (in Dollars per share)	6.14
Weighted Average Grant Date Fair Value, Vested (in Dollars per share)	6.94
Weighted Average Grant Date Fair Value, Cancelled (in Dollars per share)	5.84
Weighted Average Grant Date Fair Value, Ending Balance (in Dollars per share)	$ 6.32	$ 6.32
Weighted average remaining contractual term for the restricted stock units outstanding (in years)	1 year 2 months 12 days
Aggregate pre-tax intrinsic value of restricted stock units outstanding which includes performance based awards which are subject to milestone attainments \| $	$ 32.7	$ 32.7
Aggregate pretax intrinsic value \| $	$ 11.0
Performance-Based MSU
Class of Stock [Line Items]
Grants in period, fair value \| $		4.7
Value of shares expired unvested in period \| $		$ 2.9
Performance-Based MSU \| First Vesting period
Class of Stock [Line Items]
Award performance period	2 years
Performance-Based MSU \| First Vesting period \| Minimum
Class of Stock [Line Items]
Vesting percentage	0.00%
Performance-Based MSU \| First Vesting period \| Maximum
Class of Stock [Line Items]
Vesting percentage	150.00%
Performance-Based MSU \| Second Vesting Period
Class of Stock [Line Items]
Award performance period	3 years
Performance-Based MSU \| Second Vesting Period \| Minimum
Class of Stock [Line Items]
Vesting percentage	0.00%
Performance-Based MSU \| Second Vesting Period \| Maximum
Class of Stock [Line Items]
Vesting percentage	175.00%
2011 Equity Incentive Plan \| Outstanding RSUs \| Maximum
Class of Stock [Line Items]
Vesting period, in years	4 years
Compensation Programs \| Minimum
Class of Stock [Line Items]
Award pay out percentage	0.00%
Compensation Programs \| Maximum
Class of Stock [Line Items]
Award pay out percentage	150.00%

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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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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Weighted average remaining contractual term for equity-based awards excluding options, 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 equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Percentage of vesting of share-based compensation awards.

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