Annual report pursuant to Section 13 and 15(d)

Basis of Presentation and Summary of Significant Accounting Policies - Calculation of Earnings per Share (Details)

v3.10.0.1
Basis of Presentation and Summary of Significant Accounting Policies - Calculation of Earnings per Share (Details) - shares
shares in Thousands
3 Months Ended 12 Months Ended
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
Organization, Consolidation and Presentation of Financial Statements [Abstract]                      
Weighted-average common shares outstanding - basic (shares) 21,109 21,071 21,013 20,938 21,071 21,148 21,212 21,209 21,160 21,032 20,831
Dilutive potential common shares:                      
Restricted stock (shares)                 72 141 0
Stock options (shares)                 1,125 1,000 0
Warrants (shares)                 1,017 94 0
2019 Convertible Senior Notes (shares)                 693 1,214 0
Shares used to compute diluted income per share (shares) 21,109 23,551 23,216 23,019 21,071 24,052 24,438 24,800 24,067 23,481 20,831
Potentially dilutive shares excluded from calculation due to anti-dilutive effect (shares)                 2,845 335 3,544