Annual report pursuant to Section 13 and 15(d)

Quarterly Financial Information (Summary of Quarterly Financial Information) (Parenthetical) (Details)

v3.10.0.1
Quarterly Financial Information (Summary of Quarterly Financial Information) (Parenthetical) (Details) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Dec. 31, 2017
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Selected Quarterly Financial Information [Abstract]        
Provision for income taxes $ 104,900 $ 209,845 $ 112,058 $ 181,822