XML 71 R57.htm IDEA: XBRL DOCUMENT v3.10.0.1
Stock-Based Compensation Plans (Details 6) - $ / shares
12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Restricted stock      
Restricted stock shares      
Outstanding at the beginning of the period (in shares) 133,633 136,705 147,884
Granted (in shares) 98,713 73,342 81,400
Vested (in shares) (67,832) (73,683) (88,712)
Forfeited (in shares) (4,103) (2,731) (3,867)
Outstanding at the ending of the period (in shares) 160,411 133,633 136,705
Restricted stock shares weighted average grant date fair value per share      
Outstanding at the beginning of the period (in dollars per share) $ 172.33 $ 158.51 $ 146.21
Granted (in dollars per share) 161.58 179.58 162.38
Vested (in dollars per share) 171.22 153.86 141.38
Forfeited (in dollars per share) 166.40 173.42 162.43
Outstanding at the ending of the period (in dollars per share) $ 166.33 $ 172.33 $ 158.51
Restricted stock converted from performance shares      
Restricted stock shares      
Outstanding at the beginning of the period (in shares) 233,928 176,698 98,347
Granted (in shares) 88,297 128,482 115,618
Vested (in shares) (112,230) (70,595) (36,872)
Forfeited (in shares) (757) (657) (395)
Outstanding at the ending of the period (in shares) 209,238 233,928 176,698