Fair Value of Financial Instruments (Assets and Liabilities Measured at Fair Value) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for investment, net	$ 0	$ 0
Total assets	0	0
Fixed-rate debt	0	0
Total fixed-rate debt	0	0
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for investment, net	0	0
Total assets	0	0
Fixed-rate debt	0	0
Total fixed-rate debt	0	0
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for investment, net	1,024,712	932,343
Total assets	1,024,712	932,343
Fixed-rate debt	261,717	293,512
Total fixed-rate debt	261,717	293,512
Carrying Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for investment, net	922,530	843,781
Total assets	922,530	843,781
Fixed-rate debt	271,367	300,706
Total fixed-rate debt	271,367	300,706
Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for investment, net	1,024,712	932,343
Total assets	1,024,712	932,343
Fixed-rate debt	261,717	293,512
Total fixed-rate debt	$ 261,717	$ 293,512