Annual report pursuant to Section 13 and 15(d)

Interest Rate Derivatives (Details)

v3.6.0.2
Interest Rate Derivatives (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Effect of interest rate derivatives on consolidated statements of operations and comprehensive income      
Amount of losses recognized in AOCI (effective portion) $ (2,915) $ (4,739) $ (7,799)
Interest expense [Member]      
Effect of interest rate derivatives on consolidated statements of operations and comprehensive income      
Amount of losses reclassified from AOCI into interest rate derivatives 4,230 3,599 2,990
Loss on early extinguishment of debt [Member]      
Effect of interest rate derivatives on consolidated statements of operations and comprehensive income      
Amount of losses reclassified from AOCI into interest rate derivatives 0 0 38
Interest rate swaps      
Effect of interest rate derivatives on consolidated statements of operations and comprehensive income      
Amount of losses recognized in AOCI (effective portion) (2,915) (4,739) (7,799)
Approximate amount of losses to be reclassified from AOCL to interest expense over the next 12 months 3,900    
Interest rate derivatives in liability position, fair value 1,600    
Termination value to settle obligations under interest rate derivative agreements 1,900    
Interest rate swaps | Interest expense [Member]      
Effect of interest rate derivatives on consolidated statements of operations and comprehensive income      
Amount of losses reclassified from AOCI into interest rate derivatives 4,230 3,599 2,990
Amount of gain (loss) recognized in interest expense (ineffective portion) 378 (386) 0
Interest rate swaps | Loss on early extinguishment of debt [Member]      
Effect of interest rate derivatives on consolidated statements of operations and comprehensive income      
Amount of losses reclassified from AOCI into interest rate derivatives 0 0 $ 38
Interest rate swaps | Prepaid expenses and other assets [Member]      
Fair value of interest rate derivatives and balance sheet classification      
Interest rate swaps designated as cash flow hedges 158 53  
Interest rate swaps | Interest rate derivatives [Member]      
Fair value of interest rate derivatives and balance sheet classification      
Interest rate swaps designated as cash flow hedges (1,572) (3,160)  
Designated [Member]      
Fair values of interest rate swap derivatives      
Fair value of interest rate swaps (1,414) (3,107)  
Designated [Member] | Interest rate swap, effective date September 1, 2015, swap one [Member]      
Fair values of interest rate swap derivatives      
Notional Amount $ 100,000    
Fixed Rate (as a percent) 1.673%    
Fair value of interest rate swaps $ (701) (1,217)  
Designated [Member] | Interest rate swap, effective date September 1, 2015, swap two [Member]      
Fair values of interest rate swap derivatives      
Notional Amount $ 100,000    
Fixed Rate (as a percent) 1.73%    
Fair value of interest rate swaps $ (848) (1,429)  
Designated [Member] | Interest rate swap, effective October 1, 2015 [Member]      
Fair values of interest rate swap derivatives      
Notional Amount $ 13,586    
Fixed Rate (as a percent) 1.39%    
Fair value of interest rate swaps $ 100 53  
Notional amount after scheduled amortization 12,100    
Designated [Member] | Interest rate swap, effective September 1, 2016, swap one [Member]      
Fair values of interest rate swap derivatives      
Notional Amount $ 100,000    
Fixed Rate (as a percent) 1.9013%    
Fair value of interest rate swaps $ (23) (138)  
Designated [Member] | Interest rate swap, effective September 1, 2016, swap two [Member]      
Fair values of interest rate swap derivatives      
Notional Amount $ 100,000    
Fixed Rate (as a percent) 1.905%    
Fair value of interest rate swaps $ 48 (45)  
Designated [Member] | Interest rate swap, effective September 1, 2016, swap three [Member]      
Fair values of interest rate swap derivatives      
Notional Amount $ 50,000    
Fixed Rate (as a percent) 1.9079%    
Fair value of interest rate swaps $ 10 (32)  
Designated [Member] | Interest rate swap, effective date September 2, 2014, swap one [Member]      
Fair values of interest rate swap derivatives      
Notional Amount $ 100,000    
Fixed Rate (as a percent) 0.8055%    
Fair value of interest rate swaps $ 0 (148)  
Designated [Member] | Interest rate swap, effective date September 2, 2014, swap two [Member]      
Fair values of interest rate swap derivatives      
Notional Amount $ 100,000    
Fixed Rate (as a percent) 0.81%    
Fair value of interest rate swaps $ 0 $ (151)