XML 65 R49.htm IDEA: XBRL DOCUMENT v3.8.0.1
Long-Term Debt (Detail Textuals 2) - Uncommitted letter of credit facility - USD ($)
$ in Millions
Jan. 04, 2016
Dec. 31, 2017
Dec. 31, 2016
Line of Credit Facility [Line Items]      
Term of line of credit facility 1 year    
Amount of credit facility $ 35.0    
Commitment fee percentage, per annum on outstanding letters of credit 0.75%    
Available borrowing under the facility $ 125.0    
Letter of credit outstanding amount   $ 19.6 $ 19.1