Annual report pursuant to Section 13 and 15(d)

Stock-Based Awards Stock-Based Awards (Summary of Status of Nonvested PSUs) (Details)

v3.6.0.2
Stock-Based Awards Stock-Based Awards (Summary of Status of Nonvested PSUs) (Details) - Performance Shares [Member] - $ / shares
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares   231,602
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value $ 67.35 $ 82.67
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period 184,580  
Granted, weighted average grant date fair value (in usd per share) $ 54.06  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period (57,049)  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value $ 78.04  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period (69,557)  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value $ 74.31  
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number 295,386  
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum 200.00%  
Dividend equivalents [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period 5,810  
Granted, weighted average grant date fair value (in usd per share) $ 0.00