XML 77 R64.htm IDEA: XBRL DOCUMENT v3.8.0.1
Derivatives - Location and Aggregate Fair Value of Interest Rate Swaps (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2018
Mar. 31, 2018
Mar. 31, 2018
Jul. 07, 2016
Derivative [Line Items]        
Total notional amount   $ 250,000    
Effective date Jul. 07, 2016      
Maturity date Jun. 10, 2023      
Unsecured Debt | London Interbank Offered Rate (LIBOR) | Interest Rate Swap        
Derivative [Line Items]        
Effective fixed interest rate 1.07%   2.87% 1.07%
$250 million unsecured term borrowing bearing fixed interest of 2.87%, due June 2023 | Unsecured Debt | London Interbank Offered Rate (LIBOR)        
Derivative [Line Items]        
Effective fixed interest rate     1.07%  
Reference rate (as a percent) 1.80%      
Carrying Amount | Recurring basis | Interest Rate Swap        
Derivative [Line Items]        
Asset balance, end of period $ 18,976      
Asset balance, start of period $ 14,693