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Equity-Based Compensation (Details Textual) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Unvested Dividend Equivalent Value $ 1.9    
Equity-based compensation expense recognized 10.1 $ 8.8 $ 9.1
Unrecognized compensation expense for nonvested awards $ 10.2    
Weighted average vesting period 16 months    
Restricted Stock [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Common stock reserved for issuance pursuant to employee and director compensation programs 3,710,220    
Shares paid for tax withholding 42,347 46,941 62,291
Awards granted, shares 377,766 702,309 151,789
Equity-based compensation awards which could vest if certain targets are met 505,000    
Share based Compensation Arrangement by Share based Payment Award Number of Equivalent Dividends Issued     1,793
Employee Stock [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Common stock reserved for issuance pursuant to employee and director compensation programs 1,000,000    
Employee stock purchase plan maximum contribution 10.00%    
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent 85.00%    
Stock Issued During Period, Shares, Employee Stock Purchase Plans 39,545 46,836 24,882
Rose Rock Midstream L P [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Equity-based compensation expense recognized   $ 1.2 $ 1.4
Rose Rock Midstream L P [Member] | Restricted Stock [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares paid for tax withholding   254 12,892
Director [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based Goods and Nonemployee Services Transaction, Securities Issued 0 2,676  
Rose Rock merger agreement [Member] | Restricted Stock [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Awards granted, shares   128,585