Agreements and Transactions with Related Parties - Narratives (Details) - USD ($) $ / shares in Units, $ in Millions	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Acquisitions and Disposition Fees
Preferred return by advisor	5.00%
Interest rate on unpaid deferred acquisition fees	5.00%
Asset Management Fees and Available Cash Distributions
Net asset value (usd per share)		$ 10.11
Percentage of asset management fees paid in cash	100.00%	50.00%
Percentage of asset management fees paid in shares		50.00%
Common stock shares outstanding, shares	348,318,611	343,575,840
Percentage of available cash distribution to advisor	10.00%
Personnel And Office Rent Reimbursement
Maximum personnel and overhead reimbursement, percentage	2.00%	2.20%
Legal fee reimbursement rate	0.25%
Due from affiliate		$ 0.9
Advisor
Asset Management Fees and Available Cash Distributions
Common stock shares outstanding, shares	13,919,229
Percentage of total common stock outstanding held by related party	4.00%
Average invested assets
Personnel And Office Rent Reimbursement
Percentage of operating expenses reimbursements	2.00%
Adjusted net income
Personnel And Office Rent Reimbursement
Percentage of operating expenses reimbursements	25.00%
Minimum
Personnel And Office Rent Reimbursement
Ownership interest, percentage	6.00%
Minimum \| Average equity value
Asset Management Fees and Available Cash Distributions
Percentage of asset management fees	1.50%
Maximum
Acquisitions and Disposition Fees
Interest rate on unpaid deferred acquisition fees	6.00%
Personnel And Office Rent Reimbursement
Ownership interest, percentage	97.00%
Maximum \| Real estate commission
Acquisitions and Disposition Fees
Percentage of subordinated disposition fees	50.00%
Maximum \| Contract sales price of investment
Acquisitions and Disposition Fees
Percentage of subordinated disposition fees	3.00%
Maximum \| Average equity value
Asset Management Fees and Available Cash Distributions
Percentage of asset management fees	1.75%
Long-term net lease
Acquisitions and Disposition Fees
Percentage of acquisition fees	4.50%
Long-term net lease \| Average market value
Asset Management Fees and Available Cash Distributions
Percentage of asset management fees	0.50%
Long-term net lease \| Current
Acquisitions and Disposition Fees
Percentage of acquisition fees	2.50%
Long-term net lease \| Deferred
Acquisitions and Disposition Fees
Percentage of acquisition fees	2.00%
Non-long term net lease \| Minimum
Acquisitions and Disposition Fees
Percentage of acquisition fees	1.00%
Non-long term net lease \| Maximum
Acquisitions and Disposition Fees
Percentage of acquisition fees	1.75%

Under the terms of the advisory agreements, percentage of total performance fees that is receivable in cash.

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Under the terms of the advisory agreements, percentage of total performance fees that is receivable in restricted shares.

+ References

No definition available.

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The percentage of total investment cost reimbursable to the advisor for legal fees.

+ References

No definition available.

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The percentage threshold for personnel and overhead reimbursement chargeable by the advisor for personnel cost. Personnel expenses excludes costs related to the advisor’s legal transaction group allocated. The threshold is based on pro rata revenue.

+ References

No definition available.

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- Definition

The percentage fee paid to the advisor for managing the company's assets based on the average market value or average equity value, as applicable, depending on the type of investments.

+ References

No definition available.

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- Definition

The maximum percentage of available cash generated from operations, excluding capital proceeds, as reduced by operating expenses and debt service, excluding prepayments and balloon payments, of the operating partnership that is paid to the advisor for service fees.

+ References

No definition available.

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- Definition

The percentage guideline for when the advisor is required to reimburse the amount of operating expenses that exceeds the greater of the percentages for average invested assets or adjusted net income.

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No definition available.

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The percentage fee based on the lesser of competitive real estate commission or the contract sales prices of the investment being sold that is paid to the advisor for services provided in connection with disposition.

+ References

No definition available.

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- Definition

The percentage of our common stock outstanding held by our advisor.

+ References

No definition available.

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- Definition

The percentage of fees paid to the advisor for the structuring and negotiating investments on the company's behalf and based on the aggregate total costs of an investment for all investments other than those in readily-marketable real estate securities purchased in the secondary market.

+ References

No definition available.

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- Definition

The advisor's preferred non-compounded cumulative distribution return per annum.

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No definition available.

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No definition available.

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The annual interest rate charged to affiliates on the unpaid balance of transaction fees.

+ References

No definition available.

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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- Definition

For an unclassified balance sheet, amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Net asset value per share or per unit of investments in certain entities that calculate net asset value per share. Includes, but is not limited to, by unit, membership interest, or other ownership interest. Investment includes, but is not limited to, investment in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds. Excludes fair value disclosure.

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