Line of Credit Additional Borrowing Capacity, Under Certain Circumstances

No definition available.

Name:	arct_LineofCreditAdditionalBorrowingCapacityUnderCertainCircumstances
Namespace Prefix:	arct_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Commitment Fee Percentage, Threshold, Unused Capacity as a Percentage of Current Capacity

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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 210.5-02.22(a)(1))

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

+ Details

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Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_LineOfCreditFacilityLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Credit Facility (Details) (USD $)	3 Months Ended
Credit Facility (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Apr. 14, 2014
Line of Credit Facility [Line Items]
Credit facility	635,000,000us-gaap_LineOfCredit	$ 635,000,000us-gaap_LineOfCredit
Credit facility
Line of Credit Facility [Line Items]
Credit facility	305,000,000	330,000,000
Effective interest rate	2.09%	2.05%
Remaining borrowing capacity	18,100,000
Credit facility \| LIBOR
Line of Credit Facility [Line Items]
Unused capacity commitment fee percentage threshold	50.00%
Below Threshold \| Credit facility \| LIBOR
Line of Credit Facility [Line Items]
Unused capacity fee percentage	0.15%
Above Threshold \| Credit facility \| LIBOR
Line of Credit Facility [Line Items]
Unused capacity fee percentage	0.25%
Line of Credit Facility, Interest Rate, Option One \| Credit facility \| Maximum \| LIBOR
Line of Credit Facility [Line Items]
Spread on variable rate basis	2.25%
Line of Credit Facility, Interest Rate, Option One \| Credit facility \| Minimum \| LIBOR
Line of Credit Facility [Line Items]
Spread on variable rate basis	1.50%
Line of Credit Facility, Interest Rate, Option Two \| Credit facility \| Maximum \| Base Rate
Line of Credit Facility [Line Items]
Spread on variable rate basis	1.25%
Line of Credit Facility, Interest Rate, Option Two \| Credit facility \| Minimum \| Base Rate
Line of Credit Facility [Line Items]
Spread on variable rate basis	0.50%
Line of Credit Facility, Base Rate, Option Two \| Credit facility \| Federal Funds Effective Rate
Line of Credit Facility [Line Items]
Spread on variable rate basis	0.50%
Line of Credit Facility, Base Rate, Option Three \| Credit facility \| One-Month LIBOR
Line of Credit Facility [Line Items]
Spread on variable rate basis	1.00%
Operating Partnership Unit
Line of Credit Facility [Line Items]
Maximum capacity on credit facility			705,000,000
Additional borrowing capacity under certain circumstances			1,000,000,000
Operating Partnership Unit \| Line of Credit
Line of Credit Facility [Line Items]
Maximum capacity on credit facility			400,000,000
Operating Partnership Unit \| Credit facility
Line of Credit Facility [Line Items]
Maximum capacity on credit facility			$ 305,000,000