XML 93 R77.htm IDEA: XBRL DOCUMENT v3.20.4
Business Segment Information (Schedule of Revenues And Assets Based On Location) (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2020
Sep. 30, 2020
Jun. 30, 2020
Mar. 31, 2020
Dec. 31, 2019
Sep. 30, 2019
Jun. 30, 2019
Mar. 31, 2019
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]                      
Revenues $ 443,723 $ 424,927 $ 400,646 $ 414,762 $ 423,225 $ 416,254 $ 409,586 $ 400,820 $ 1,684,058 $ 1,649,885 $ 1,624,167
Assets 2,167,256       2,151,370       2,167,256 2,151,370  
United States                      
Revenues from External Customers and Long-Lived Assets [Line Items]                      
Revenues                 1,427,152 1,385,744 1,348,130
Assets 1,772,179       1,732,427       1,772,179 1,732,427  
International operations                      
Revenues from External Customers and Long-Lived Assets [Line Items]                      
Revenues                 256,906 264,141 $ 276,037
Assets $ 395,077       $ 418,943       $ 395,077 $ 418,943