XML 55 R43.htm IDEA: XBRL DOCUMENT v3.7.0.1
Stockholders' Equity - Stock Options Exercise Data (Details) - Stock Options - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Summary of stock option exercise data    
Number of options exercised (in shares) 334,065 81,105
Cash received $ 33.0 $ 2.6
Total intrinsic value of options exercised $ 20.3 $ 7.6