Summary of Business Organization, Operations and Significant Accounting Policies - Stock Based Compensation (Details)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk free interest rates	1.79%	2.44%	2.84%
Expected volatility	41.00%	41.00%	40.00%
Expected dividend rate	13.11%	8.47%	8.70%
Stock Options \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term	4 years	4 years	4 years
Stock Options \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term	5 years	5 years	5 years
Restricted Stock Award
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk free interest rates	0.85%	2.53%	2.58%
Expected volatility	30.30%	43.70%	44.50%
Beta	1.12	1.00	1.05

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Beta

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the 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.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ 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
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-Name Accounting Standards Codification
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-Section S99
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