XML 123 R58.htm IDEA: XBRL DOCUMENT v3.19.3
Share-Based Compensation - Valuation Assumptions (Details) - $ / shares
9 Months Ended
Sep. 30, 2019
Sep. 30, 2018
Equity [Abstract]    
Risk-free interest rate 2.49% 2.67%
Expected life in years 5 years 10 months 24 days 6 years
Expected volatility 20.00% 20.00%
Expected dividend yield 1.44% 1.43%
Estimated weighted-average fair value of options granted per share (in dollars per share) $ 15.45 $ 14.08