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Share-Based Compensation - Fair Value Assumptions of Stock Options (Details) - BYB Plan - $ / shares | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015
Time Options Grants |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Risk-free interest rate, minimum | 1.34% | 1.68%
Risk-free interest rate, maximum | 1.40% | 1.85%
Expected stock price volatility | 20.39% |
Expected stock price volatility, minimum |  | 16.18%
Expected stock price volatility, maximum |  | 16.55%
Expected dividend yield | 0.00% | 0.00%
Weighted average grant date fair value | $ 3.55 | $ 2.25
Time Options Grants | Minimum |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Expected term (years) | 5 years 2 months 12 days | 5 years 8 months 12 days
Time Options Grants | Maximum |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Expected term (years) | 5 years 7 months 6 days | 6 years 3 months 18 days
Performance Options Grants |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Risk-free interest rate | Implied forward rates | Implied forward rates
Expected term (years) | Variable | Variable
Expected stock price volatility, minimum | 20.34% | 16.18%
Expected stock price volatility, maximum | 20.39% | 16.55%
Expected dividend yield | 0.00% | 0.00%
Weighted average grant date fair value | $ 3.75 | $ 1.65

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- Definition Share based compensation arrangement by share based payment award fair value assumptions risk free interest rate description. + References No definition available. + Details
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- Definition Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award. + References No definition available. + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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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. + Details
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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 The maximum risk-free interest rate assumption that is used in valuing an option on its own shares. + References No definition available. + Details
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- Definition The minimum risk-free interest rate assumption that is used in valuing an option on its own shares. + 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. + References No definition available. + Details
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- Definition Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.D.2) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 + Details
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