Annual report pursuant to Section 13 and 15(d)

Derivatives - Summary of Outstanding Swaps (Details)

v3.8.0.1
Derivatives - Summary of Outstanding Swaps (Details)
12 Months Ended
Dec. 31, 2017
USD ($)
1.884 % interest rate swaps  
Derivative [Line Items]  
Notional $ 518,375,000
Fixed Rate Paid 1.884%
Variable interest rate base floor 1.00%
Variable interest rate base 3 mo.USD-LIBOR-BBA
1.384 % interest rate swaps  
Derivative [Line Items]  
Notional $ 137,387,500
Fixed Rate Paid 1.384%
Variable interest rate base floor 1.00%
Variable interest rate base 3 mo.USD-LIBOR-BBA
1.959 % interest rate swaps  
Derivative [Line Items]  
Notional $ 107,412,060
Fixed Rate Paid 1.959%
Variable interest rate base floor 1.00%
Variable interest rate base 3 mo.USD-LIBOR-BBA
1.850 % interest rate swaps  
Derivative [Line Items]  
Notional $ 107,412,060
Fixed Rate Paid 1.85%
Variable interest rate base floor 1.00%
Variable interest rate base 3 mo.USD-LIBOR-BBA
3.110 % interest rate swaps  
Derivative [Line Items]  
Notional $ 191,475,002
Fixed Rate Paid 3.11%
Variable interest rate base floor 1.00%
Variable interest rate base 3 mo.USD-LIBOR-BBA
3.110% interest rate swaps  
Derivative [Line Items]  
Notional $ 250,000,000
Fixed Rate Paid 3.11%
Variable interest rate base floor 1.00%
Variable interest rate base 3 mo.USD-LIBOR-BBA
2.504 % interest rate swaps  
Derivative [Line Items]  
Notional $ 50,000,000
Fixed Rate Paid 2.504%
Variable interest rate base floor 1.00%
Variable interest rate base 3 mo.USD-LIBOR-BBA
1.833 % interest rate swaps  
Derivative [Line Items]  
Notional $ 377,000,000
Fixed Rate Paid 1.833%
Variable interest rate base floor 1.00%
Variable interest rate base 3 mo.USD-LIBOR-BBA