Share-based Compensation - Compensation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Summary of changes in restricted stock outstanding
Total share-based compensation	$ 455	$ 12,848
Capitalized share-based compensation	(1,438)	(1,597)
Total share-based compensation expense	(983)	11,251
Weighted Average Grant Date Fair Value Per Share
Share-based compensation liability	7,548	7,548	$ 1,815
Equity awards
Summary of changes in restricted stock outstanding
Total share-based compensation expense	(1,724)	10,716
Liability awards
Summary of changes in restricted stock outstanding
Total share-based compensation expense	$ 2,179	$ 2,132
Restricted stock
Shares
Non-vested at beginning of the year (in shares)		9,104
Granted (in shares)		1,369
Vested (in shares)		(123)
Forfeited (in shares)		(1,934)
Non-vested at end of the year (in shares)	8,416	8,416
Weighted Average Grant Date Fair Value Per Share
Non-vested at beginning of the year (in dollars per share)		$ 10.15
Granted (in dollars per share)		7.76
Vested (in dollars per share)		8.16
Forfeited (in dollars per share)		10.20
Non-vested at end of the year (in dollars per share)	$ 8.95	$ 8.95
FID Bonus
Weighted Average Grant Date Fair Value Per Share
Percentage of FID bonus to be settled in shares of common stock		110.00%
Share-based compensation liability	$ 800	$ 800

Percentage of FID bonus whereby the FID bonus will be settled in shares of common stock.

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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 payable within one year (or the operating cycle, if longer).

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

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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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Amount of capitalized and expensed compensation cost from equity-based compensation arrangements.

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