Stock-based Compensation Plans and Awards - Employee Stock Purchase Plan - (Details) - Employee Stock Purchase Plan	1 Months Ended	12 Months Ended
May 31, 2011	Dec. 31, 2019 item shares
Stock-based Compensation
Discount (as a percent)	15.00%
Duration of each purchase period		6 months
Participants maximum payroll deductions (as a percent)		15.00%
Duration of each offering period		12 months
Number of purchase periods in each offering period \| item		2
Maximum number of common stock shares that may be purchased by each participant		500
Fair value assumptions, expected volatility, minimum (as a percent)		27.00%
Fair value assumptions, expected volatility, maximum (as a percent)		47.00%
Number of common stock shares remaining authorized for issuance		1,600,000

Duration of offering period of share-based compensation arrangement under terms of plan.

No definition available.

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- Definition

Duration of purchase period of share-based compensation arrangement under terms of plan.

+ References

No definition available.

+ Details

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- Definition

Number of purchase periods of share-based compensation arrangement under terms of plan.

+ References

No definition available.

+ Details

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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

No definition available.

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- Definition

The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

No definition available.

+ Details

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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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No definition available.

+ Details

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

+ Details

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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

+ References

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- Definition

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.

+ References

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