XML 19 R4.htm IDEA: XBRL DOCUMENT v3.8.0.1
CONSOLIDATED STATEMENTS OF COMPREHENSIVE EARNINGS (Parentheticals) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Statement of Comprehensive Income [Abstract]      
Postretirement benefit plan remeasurement, tax expense $ 29,172    
Postretirement benefit plan reclassification, tax (expense) benefit $ (1,017) $ 6,991 $ (17,013)