Stock-Based Compensation (Details) - Long Term Incentive Plan $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2019 USD ($) $ / shares shares
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted (in shares)	0
Award vesting period	3 years
Unrecognized compensation costs \| $	$ 400
Performance Shares \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion ratio, percent of target	0.00%
Performance Shares \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion ratio, percent of target	200.00%
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Number of RSUs granted in period (in shares)	33,458
Weighted-average grant date fair value (in dollars per share) \| $ / shares	$ 65.32
Unrecognized compensation costs \| $	$ 3,700
Unrecognized Compensation Cost, Period for Recognition	through 2024
A 2018 Award and 2019 Award [Member] \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense \| $	$ 0
Target Achieved [Member] \| A 2018 Award [Member] \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Award Target Share	31,825
Target Achieved [Member] \| A 2019 Award [Member] \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Award Target Share	35,170

The target number of shares to be awarded under the plan if performance goals are achieved.

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- Definition

Share-based Compensation Arrangements by Share-based Payment Award, Conversion Ratio, Percent of Target

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The maximum vesting term over 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.

+ References

No definition available.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based compensation awards.

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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 of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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- Definition

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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Net number of non-option equity instruments granted to participants.

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