Share Repurchases (Notes)

9 Months Ended

Sep. 30, 2017

Equity, Class of Treasury Stock [Line Items]

Treasury Stock [Text Block]

In July 1998, the company's Board of Directors adopted a stock repurchase program and subsequently authorized the purchase of common shares in open market purchases. During 2013, the company's Board of Directors authorized the purchase of additional common shares in open market purchases. For the three months period ended September 30, 2017 the company repurchased 1,680,395 shares of its common stock under the program for $200.4 million, including applicable commissions, which represented an average price of $119.23. As of September 30, 2017, the total number of shares authorized for repurchase under the program is 4,570,266. As of September 30, 2017, 3,860,996 shares had been purchased under the 1998 stock repurchase program.