Quarterly report pursuant to Section 13 or 15(d)

Earnings Per Share (Schedule of Earnings Per Share Reconciliation) (Details)

v3.10.0.1
Earnings Per Share (Schedule of Earnings Per Share Reconciliation) (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Basic:        
Net income - basic $ 111,319 $ 105,936 $ 201,409 $ 260,391
Net income - basic (in shares) 173,623,630 182,840,213 177,158,230 176,591,166
Net income - basic (in usd per share) $ 0.64 $ 0.58 $ 1.14 $ 1.47
Effect of dilutive securities:        
Stock options and awards $ 0 $ 0 $ 0 $ 0
Stock options and awards (in shares) 516,997 1,517 579,052 251,073
Diluted:        
Net income - diluted $ 111,319 $ 105,936 $ 201,409 $ 260,391
Net income - diluted (in shares) 174,140,627 182,841,730 177,737,282 176,842,239
Net income - diluted (in usd per share) $ 0.64 $ 0.58 $ 1.13 $ 1.47