Equity Compensation Plans - Restricted Stock and RSUs (Details) - Restricted Stock and Restricted Stock Units [Member] $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended
Mar. 31, 2020 USD ($) $ / shares shares	Mar. 31, 2020 USD ($) $ / shares shares
Changes in unvested awards
Nonvested at the beginning of the period (in shares) \| shares		555,283
Granted (in shares) \| shares	0	137,944
Vested (in shares) \| shares		(119,452)
Nonvested at the end of the period (in shares) \| shares	573,775	573,775
Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share) \| $ / shares		$ 12.85
Granted (in dollars per share) \| $ / shares		12.26
Vested (in dollars per share) \| $ / shares		11.00
Nonvested at the end of the period (in dollars per share) \| $ / shares	$ 13.09	$ 13.09
Additional information
Total unrecognized compensation cost of restricted awards \| $	$ 4.0	$ 4.0
Expected weighted-average period for recognition of unrecognized compensation		2 years 1 month 6 days

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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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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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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