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.

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

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-Publisher FASB
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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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No definition available.

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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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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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No definition available.

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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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-Name Accounting Standards Codification
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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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- 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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No definition available.

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Percentage of vesting of share-based compensation awards.

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Stock-Based Compensation Plans (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended			3 Months Ended		9 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Stock-Based Compensation Plans
Unrecognized compensation cost	$ 7.7			$ 7.7		$ 7.7
Weighted average life over which unrecognized compensation is expected to be recognized						1 year 1 month 13 days
General and administrative expenses
Stock-Based Compensation Plans
Stock-based compensation expense				$ 1.3	$ 1.2	$ 4.0	$ 3.2
Restricted stock awards
Number of Shares
Unvested at the beginning of the period (in shares)						1,114,625
Granted (in shares)			259,800			288,240
Vested (in shares)						(373,599)
Unvested at the end of the period (in shares)	1,029,266			1,029,266		1,029,266
Weighted-Average Grant-Date Fair Value
Unvested at the beginning of the period (in dollars per share)						$ 17.72
Granted (in dollars per share)						7.36
Vested (in dollars per share)						16.59
Unvested at the end of the period (in dollars per share)	$ 15.23			$ 15.23		$ 15.23
Restricted stock awards \| Vest immediately
Stock-Based Compensation Plans
Vesting (as a percent)			25.00%
Restricted stock awards \| Vest one year after grant
Stock-Based Compensation Plans
Vesting (as a percent)			25.00%
Restricted stock awards \| Vest two years after grant
Stock-Based Compensation Plans
Vesting (as a percent)			25.00%
Restricted stock awards \| Vest three years after grant
Stock-Based Compensation Plans
Vesting (as a percent)			25.00%
Non-executive director \| Restricted stock awards
Number of Shares
Granted (in shares)	8,095	8,385	7,220
Non-employee consultant \| Restricted stock awards
Number of Shares
Granted (in shares)	1,619	1,677	1,444