Summary of Significant Accounting Policies - Schedule of Restricted Cash and Escrow Deposits (Details) - USD ($) $ in Thousands |
Sep. 30, 2017 |
Dec. 31, 2016 |
|---|---|---|
| Restricted Cash and Cash Equivalents Items [Line Items] | ||
| Restricted cash and deposits in escrow | $ 96,344 | $ 26,839 |
| Collateral deposits | ||
| Restricted Cash and Cash Equivalents Items [Line Items] | ||
| Restricted cash and deposits in escrow | 1,229 | 1,374 |
| Tenant improvements, repairs, and leasing commissions | ||
| Restricted Cash and Cash Equivalents Items [Line Items] | ||
| Restricted cash and deposits in escrow | 7,988 | 9,739 |
| Master Trust Release | ||
| Restricted Cash and Cash Equivalents Items [Line Items] | ||
| Restricted cash and deposits in escrow | 79,353 | 14,412 |
| Loan impounds | ||
| Restricted Cash and Cash Equivalents Items [Line Items] | ||
| Restricted cash and deposits in escrow | 330 | 670 |
| Other | ||
| Restricted Cash and Cash Equivalents Items [Line Items] | ||
| Restricted cash and deposits in escrow | $ 7,444 | $ 644 |