XML 92 R70.htm IDEA: XBRL DOCUMENT v3.3.1.900
Earnings Per Share - Details of Basic and Diluted Earnings Per Share (EPS) (Detail) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2015
Sep. 30, 2015
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Earnings Per Share [Abstract]                      
Net income                 $ 64,575 $ 69,246 $ 67,158
Weighted average common shares outstanding used in basic EPS                 43,397 43,201 43,158
Common shares issuable upon exercise of dilutive stock options and PSAs / RSUs                 545 865 1,141
Weighted average common shares outstanding and common share equivalents used in diluted EPS                 43,942 44,066 44,299
Earnings per share                      
Basic                 $ 1.49 $ 1.60 $ 1.56
Diluted $ 0.78 $ 0.31 $ 0.06 $ 0.32 $ 0.45 $ 0.69 $ 0.11 $ 0.33 $ 1.47 $ 1.57 $ 1.52