Stock Based Compensation - Schedule of Restricted Stock Units (Details) - The 2009 Stock Incentive Plan - Restricted Stock - $ / shares shares in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Number of Awards
Unvested RSU Awards Outstanding beginning of period (in shares)	360	472	32
Granted (in shares)	6	0	472
Vested (in shares)	(119)	(112)	(32)
Unvested RSU Awards Outstanding end of period (in shares)	247	360	472
Weighted Average Grant Date Fair Value per Award
Unvested RSU Awards Outstanding beginning of period (in dollars per share)	$ 24.82	$ 24.82	$ 39.80
Granted (in dollars per share)	18.71	0	24.82
Vested (in dollars per share)	18.05	22.70	39.80
Unvested RSU Awards Outstanding end of period (in dollars per share)	$ 24.82	$ 24.82	$ 24.82

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).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
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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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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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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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- Definition

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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