Equity Compensation Plans - Restricted Stock and RSUs (Details) - Restricted Stock and Restricted Stock Units [Member] - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Changes in unvested awards
Nonvested at the beginning of the period (in shares)	552,281
Granted (in shares)	171,356	254,281
Vested (in shares)	(168,354)
Nonvested at the end of the period (in shares)	555,283	552,281
Weighted Average Grant Date Fair Value
Nonvested at the beginning of the period (in dollars per share)	$ 11.30
Granted (in dollars per share)	12.75
Vested (in dollars per share)	7.68
Nonvested at the end of the period (in dollars per share)	$ 12.85	$ 11.30
Additional information
Total unrecognized compensation cost of restricted awards	$ 3.0
Expected weighted-average period for recognition of unrecognized compensation	1 year 9 months 29 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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