Stock-based Compensation - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award
Stock-based compensation	$ 3,155,000	$ 3,836,000
Expected cost on shares expected to vest	$ 3,576,000
Recognition period for compensation expense not yet recognized	3 years 2 months 12 days
Weighted average shares granted (usd per share)	$ 18.63	$ 27.05
Fully Vested and Restricted Stock \| Director
Share-based Compensation Arrangement by Share-based Payment Award
Stock-based compensation	$ 526,000	$ 880,000
Granted (shares)	21,532	24,427
Weighted average shares granted (usd per share)	$ 24.38	$ 23.64
Deferred Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Granted (shares)	12,304	14,914
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Granted (shares)	62,125	62,320
Restricted Stock \| Vesting period one
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period	4 years
Restricted Stock \| Vesting period two
Share-based Compensation Arrangement by Share-based Payment Award
Vesting period	3 years
Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Granted (shares)	89,092	65,421
Vesting period	3 years
Restricted Stock And Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award
Stock-based compensation	$ 2,630,000	$ 2,956,000
Omnibus Plan
Share-based Compensation Arrangement by Share-based Payment Award
Stock-based compensation	$ 0	$ 0
Share-based compensation, number of shares authorized (shares)	2,058,000
Shares granted in period (shares)	0	0

Unrecognized cost of unvested share-based compensation awards.

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- Definition

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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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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 maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Gross number of share options (or share units) granted during the period.

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