Agreements and Transactions with Related Parties - Narratives (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Acquisitions and Disposition Fees
Advisory agreement, term	1 year
Preferred return by advisor (as a percentage)	5.00%
Interest rate on unpaid deferred acquisition fees (as a percentage)	5.00%
Asset Management Fees and Available Cash Distributions
Net asset value (usd per share)		$ 10.04
Asset management fees paid in cash (as a percentage)	100.00%	100.00%
Common stock shares outstanding, shares	351,499,230	349,899,827
Available cash distribution to advisor (as a percentage)	10.00%
Personnel And Office Rent Reimbursement
Personnel and overhead reimbursement (as a percentage)	1.00%	2.00%
Legal fee reimbursement rate (as a percentage)	0.25%
Due from affiliate		$ 0.2
Advisor
Asset Management Fees and Available Cash Distributions
Common stock shares outstanding, shares	15,385,683
Total common stock outstanding held by related party (as a percentage)	4.40%
Average invested assets
Personnel And Office Rent Reimbursement
Operating expenses reimbursements (as a percentage)	2.00%
Adjusted net income
Personnel And Office Rent Reimbursement
Operating expenses reimbursements (as a percentage)	25.00%
Minimum
Personnel And Office Rent Reimbursement
Ownership interest (as a percentage)	6.00%
Minimum \| Average equity value
Asset Management Fees and Available Cash Distributions
Asset management fees (as a percentage)	1.50%
Maximum
Acquisitions and Disposition Fees
Interest rate on unpaid deferred acquisition fees (as a percentage)	6.00%
Personnel And Office Rent Reimbursement
Ownership interest (as a percentage)	97.00%
Maximum \| Real estate commission
Acquisitions and Disposition Fees
Subordinated disposition fees (as a percentage)	50.00%
Maximum \| Contract sales price of investment
Acquisitions and Disposition Fees
Subordinated disposition fees (as a percentage)	3.00%
Maximum \| Average equity value
Asset Management Fees and Available Cash Distributions
Asset management fees (as a percentage)	1.75%
Long-term net lease
Acquisitions and Disposition Fees
Acquisition fees (as a percentage)	4.50%
Long-term net lease \| Average market value
Asset Management Fees and Available Cash Distributions
Asset management fees (as a percentage)	0.50%
Long-term net lease \| Current
Acquisitions and Disposition Fees
Acquisition fees (as a percentage)	2.50%
Long-term net lease \| Deferred
Acquisitions and Disposition Fees
Acquisition fees (as a percentage)	2.00%
Non-long term net lease \| Minimum
Acquisitions and Disposition Fees
Acquisition fees (as a percentage)	1.00%
Non-long term net lease \| Maximum
Acquisitions and Disposition Fees
Acquisition fees (as a percentage)	1.75%

Advisory Agreement, Term

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

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

+ References

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The ownership interest in jointly owned investments by the reporting entity.

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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

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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.

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No definition available.

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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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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.

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No definition available.

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

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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.

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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.

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No definition available.

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

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

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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
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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

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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