Annual report pursuant to Section 13 and 15(d)

Capital Structure and Per Share Data - Dilutive Effect on Earnings Per Share (Details)

v3.10.0.1
Capital Structure and Per Share Data - Dilutive Effect on Earnings Per Share (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
3 Months Ended 12 Months Ended
Jan. 01, 2018
Dec. 31, 2018
Sep. 30, 2018
Jun. 30, 2018
Mar. 31, 2018
Dec. 31, 2017
Sep. 30, 2017
Jun. 30, 2017
Mar. 31, 2017
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Earnings Per Share [Abstract]                        
Weighted Average Shares (in shares)                   42,708 43,997 45,637
Weighted Average Shares, Stock compensation plans (in shares)                   242 361 311
Weighted Average Shares, Diluted (in shares)                   42,950 44,358 45,948
Income (Loss) From Continuing Operations                   $ 52,390 $ 94,153 $ 94,516
Income (Loss) From Continuing Operations, Non-vested restricted stock, Amount                   (50) (85) (52)
Income (Loss) From Continuing Operations, Basic, Amount                   52,340 94,068 94,464
Income (Loss) From Continuing Operations Diluted, Amount                   $ 52,340 $ 94,068 $ 94,464
Income (Loss) From Continuing Operations, Basic, Per Share Amount (usd per share)                   $ 1.23 $ 2.14 $ 2.07
Income (Loss) From Continuing Operations, Diluted (usd per share)                   $ 1.22 $ 2.12 $ 2.06
Income (Loss) From Discontinued Operations, Earnings (loss), Amount                   $ (740) $ (1,170) $ (1,323)
Income (Loss) From Discontinued Operations, Non-vested restricted stock, Amount                   0 0 0
Income (Loss) From Discontinued Operations, Basic earnings (loss), Amount                   (740) (1,170) (1,323)
Income (Loss) From Discontinued Operations, Diluted earnings (loss), Amount                   $ (740) $ (1,170) $ (1,323)
Income (Loss) From Discontinued Operations, Basic earnings (loss), Per Share Amount (usd per share)                   $ (0.02) $ (0.03) $ (0.03)
Income (Loss) From Discontinued Operations, Diluted earnings (loss), Per Share Amount (usd per share)                   $ (0.02) $ (0.03) $ (0.03)
Net Income (Loss), Amount $ 51,650 $ 21,821 $ 15,118 $ 16,905 $ (2,194) $ 61,952 $ 19,440 $ 12,132 $ (541) $ 51,650 $ 92,983 $ 93,193
Net Income (Loss), Non-vested restricted stock, Amount                   (50) (85) (52)
Net Income (Loss), Basic, Amount                   51,600 92,898 93,141
Net Income (Loss), Diluted, Amount                   $ 51,600 $ 92,898 $ 93,141
Earnings (loss) per common share (usd per share)   $ 0.51 $ 0.35 $ 0.40 $ (0.05) $ 1.43 $ 0.45 $ 0.27 $ (0.01) $ 1.21 $ 2.11 $ 2.04
Earnings (loss) per common share (usd per share)   $ 0.51 $ 0.35 $ 0.39 $ (0.05) $ 1.42 $ 0.44 $ 0.27 $ (0.01) $ 1.20 $ 2.09 $ 2.03