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Stock-Based Compensation - Stock Option Black Scholes Option Pricing Model Assumptions (Details) - Share-based Payment Arrangement, Option [Member]
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis, Valuation Techniques [Line Items]      
Expected volatility 31.70% 30.50% 32.50%
Risk-free interest rate 1.70% 2.80% 2.00%
Expected term (years) 6 years 1 month 6 days 6 years 1 month 6 days 5 years 6 months