Stock-Based Compensation - Narrative (Details)	6 Months Ended
Jun. 30, 2019 plan $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity compensation plans (plan) \| plan	2
Long-Term Incentive Plan [Member] \| Restricted Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares) \| shares	85,640
Shares granted, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 34.22
Shares vested (in shares) \| shares	96,625
Shares vested, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 30.47
Long-Term Incentive Plan [Member] \| Performance awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares) \| shares	72,932
Shares granted, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 39.26
Long-Term Incentive Plan [Member] \| Performance awards [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of potential target shares awarded	0.00%
Long-Term Incentive Plan [Member] \| Performance awards [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of potential target shares awarded	200.00%
Long-Term Incentive Plan [Member] \| Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares exercised (in shares) \| shares	11,507
Shares exercised, weighted average exercise price (in dollars shares) \| $ / shares	$ 24.68
Long-Term Incentive Plan [Member] \| Market based Performance Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period	2 years 9 months 18 days
Long-Term Incentive Plan [Member] \| Internal Measure based Performance Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period	2 years 9 months 18 days
Long-Term Incentive Plan [Member] \| ShareBased Payment Arrangement Employee [Member] \| Restricted Awards [Member] \| Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amortization period	3 years
Long-Term Incentive Plan [Member] \| ShareBased Payment Arrangement Employee [Member] \| Restricted Awards [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amortization period	1 year

Represents the number of equity stock based compensation plans.

No definition available.

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- Definition

The percentage of target shares, an employee can earn, under the plan.

+ References

No definition available.

+ Details

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

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.

+ References

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- Definition

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).

+ References

+ Details

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- Definition

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).

+ References

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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- Definition

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.

+ References

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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.

+ References

No definition available.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

No definition available.

+ Details

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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