Stock-Based Compensation - Additional Disclosures (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period	10 years
Unearned stock-based compensation expense not yet recognized, recognition period	2 years 1 month 10 days
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	50.00%
Award vesting period	1 year
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	150.00%
Award vesting period	3 years
Stock Options and Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unearned stock-based compensation expense not yet recognized \| $	$ 2.9
2014 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares that may be issued under plan	1,644,875
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	58,707
2016 Incentive Plan [Member] [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares that may be issued under plan	800,000
2016 Incentive Plan Amended and Restated [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares that may be issued under plan	2,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	1,147,505

Unrecognized cost of unvested share-based compensation awards.

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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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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 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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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Percentage of vesting of share-based compensation awards.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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