Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
ASSETS
Cash	$ 386	$ 178
Restricted cash	68	0
Commercial mortgage loans, held for investment, net	456,884us-gaap_LoansReceivableNet	30,832us-gaap_LoansReceivableNet
Real estate securities, at fair value	50,234us-gaap_AvailableForSaleSecurities	5,005us-gaap_AvailableForSaleSecurities
Accrued interest receivable	2,866us-gaap_InterestReceivable	126us-gaap_InterestReceivable
Prepaid expenses and other assets	3,782us-gaap_PrepaidExpenseAndOtherAssets	229us-gaap_PrepaidExpenseAndOtherAssets
Total assets	514,220us-gaap_Assets	36,370us-gaap_Assets
LIABILITIES AND STOCKHOLDERS' EQUITY
Revolving line of credit with affiliate	0us-gaap_LongTermDebt	7,305us-gaap_LongTermDebt
Interest payable	232	15
Distributions payable	2,623	216
Accounts payable and accrued expenses	2,385	1,738
Due to affiliate	2,035	1,078
Total liabilities	183,713us-gaap_Liabilities	10,352us-gaap_Liabilities
Preferred stock, $0.01 par value, 50,000,000 authorized, none issued and outstanding as of December 31, 2014 and 2013	0us-gaap_PreferredStockValue	0us-gaap_PreferredStockValue
Convertible stock (promote shares); $0.01 par value, 1,000 and 0 shares authorized, issued and outstanding as of December 31, 2014 and 2013, respectively.	1arct_ConvertibleSharesValueIssued	0arct_ConvertibleSharesValueIssued
Common stock, $0.01 par value, 949,999,000 and 950,000,000 shares authorized, 15,472,192 and 1,330,669 shares issued and outstanding as of December 31, 2014 and 2013, respectively	155us-gaap_CommonStockValue	13us-gaap_CommonStockValue
Additional paid-in capital	340,874us-gaap_AdditionalPaidInCapital	26,620us-gaap_AdditionalPaidInCapital
Accumulated other comprehensive loss	(307)	(10)
Accumulated deficit	(10,216)	(605)
Total stockholders' equity	330,507us-gaap_StockholdersEquity	26,018us-gaap_StockholdersEquity
Total liabilities and stockholders' equity	514,220	36,370
CMBS [Member]
ASSETS
Real estate securities, at fair value	50,234	5,005
LIABILITIES AND STOCKHOLDERS' EQUITY
Repurchase agreements - commercial mortgage loans	150,169	0
Real Estate Securities [Member]
LIABILITIES AND STOCKHOLDERS' EQUITY
Repurchase agreements - commercial mortgage loans	$ 26,269	$ 0

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Sum of the carrying values as of the balance sheet date of obligations incurred through that date, including liabilities incurred and payable to vendors for goods and services received, taxes, interest, rent and utilities, compensation costs, payroll taxes and fringe benefits (other than pension and postretirement obligations), contractual rights and obligations, and statutory obligations.

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Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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Amount of liabilities and equity items, including the portion of equity attributable to noncontrolling interests, if any.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets.

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The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 4.E)

-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74512-122707

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section E

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29-31)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30, 31

-Article 5

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