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Summary of Significant Accounting Policies (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Mar. 31, 2016
Entity Information [Line Items]        
Cumulative Effect of New Accounting Principle in Period of Adoption $ 15.9     $ 16.3
Maximum        
Entity Information [Line Items]        
Equity Method Investment, Ownership Percentage 50.00%      
Minimum        
Entity Information [Line Items]        
Equity Method Investment, Ownership Percentage 20.00%      
All Customers [Member] [Member]        
Entity Information [Line Items]        
Concentration Risk, Percentage 41.00% 45.00% 41.00%