XML 102 R89.htm IDEA: XBRL DOCUMENT v3.10.0.1
Related Party Transactions (Split Dollar Agreements) (Narrative) (Details) - USD ($)
$ in Millions
3 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Dec. 31, 2017
Chairman, Board of Directors [Member]      
Related Party Transaction [Line Items]      
Payments for life insurance policies $ 0.5 $ 0.5  
Chief Executive Officer [Member]      
Related Party Transaction [Line Items]      
Payments for life insurance policies 0.7 $ 0.7  
Executive Officers [Member] | Other Long-Term Assets [Member]      
Related Party Transaction [Line Items]      
Life insurance assets, carrying amount $ 17.9   $ 16.6