Percentage of LTIP Units Allowable to be Converted, Percentage

No definition available.

Name:	arct_PercentageOfSharesAllowableToBeConvertedPercentage
Namespace Prefix:	arct_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Automatic Grant

+ References

No definition available.

+ Details

Name:	arct_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAutomaticGrant
Namespace Prefix:	arct_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Performance Period

+ References

No definition available.

+ Details

Name:	arct_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePeriod
Namespace Prefix:	arct_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Periodic Vesting Percentage

+ References

No definition available.

+ Details

Name:	arct_ShareBasedCompensationArrangementByShareBasedPaymentAwardPeriodicVestingPercentage
Namespace Prefix:	arct_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Return Percentage Threshold

+ References

No definition available.

+ Details

Name:	arct_ShareBasedCompensationArrangementByShareBasedPaymentAwardReturnPercentageThreshold
Namespace Prefix:	arct_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Shares Allocated as a Percentage of Shares Authorized

+ References

No definition available.

+ Details

Name:	arct_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAllocatedAsPercentageOfSharesAuthorized
Namespace Prefix:	arct_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Shares Authorized, Percentage of Benchmark

+ References

No definition available.

+ Details

Name:	arct_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAuthorizedPercentageOfBenchmark
Namespace Prefix:	arct_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Shares Authorized, Percentage of Benchmark, Potential Share Commitment

+ References

No definition available.

+ Details

Name:	arct_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAuthorizedPercentageOfBenchmarkPotentialShareCommitment
Namespace Prefix:	arct_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Shares Authorized, Percentage of Benchmark, Shares Committed Annually

+ References

No definition available.

+ Details

Name:	arct_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAuthorizedPercentageOfBenchmarkSharesCommittedAnnually
Namespace Prefix:	arct_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Shares Authorized, Value of Benchmark

+ References

No definition available.

+ Details

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

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Shares Awarded as a Percentage of Maximum

+ References

No definition available.

+ Details

Name:	arct_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesAwardedAsPercentageOfMaximum
Namespace Prefix:	arct_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph g(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

-URI http://asc.fasb.org/extlink&oid=6793087&loc=d3e301413-122809

+ Details

Name:	us-gaap_AllocatedShareBasedCompensationExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of common shares reserved for future issuance related to deferred compensation arrangements with individuals.

+ References

No definition available.

+ Details

Name:	us-gaap_DeferredCompensationArrangementWithIndividualCommonStockReservedForFutureIssuance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

+ Details

Name:	us-gaap_ShareBasedCompensation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares reserved for issuance under non-option equity instrument agreements awarded that validly exist and are outstanding, including vested instruments.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

+ References

No definition available.

+ Details

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

- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperRangeLimit
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

+ References

No definition available.

+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesIssuedForServices
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Share-Based Compensation (Details) (USD $)	0 Months Ended	3 Months Ended			3 Months Ended						12 Months Ended		3 Months Ended		3 Months Ended		3 Months Ended		3 Months Ended		3 Months Ended		0 Months Ended	36 Months Ended															25 Months Ended
Share-Based Compensation (Details) (USD $)	Feb. 28, 2013	Mar. 31, 2013	Mar. 31, 2012	Oct. 14, 2010	Mar. 31, 2013 Restricted Stock [Member]	Mar. 31, 2012 Restricted Stock [Member]	Mar. 31, 2013 Compensation expense, accelerated vesting portion [Member] Restricted Stock [Member]	Mar. 31, 2013 2013 Advisor Multi-Year Outperformance Agreement (OPP) [Domain]	Sep. 30, 2012 Restricted Stock [Member] Restricted Share Plan [Member] Manager [Member]	Mar. 31, 2013 Restricted Stock [Member] Restricted Share Plan [Member] ARC Properties Advisors, LLC [Member] Manager [Member]	Dec. 31, 2012 Restricted Stock [Member] Restricted Share Plan [Member] ARC Properties Advisors, LLC [Member] Manager [Member]	Dec. 31, 2012 Restricted Stock [Member] Restricted Share Plan [Member]	Mar. 31, 2013 Restricted Stock [Member] Director Stock Plan [Member]	Sep. 30, 2012 Restricted Stock [Member] Director Stock Plan [Member]	Mar. 31, 2013 Restricted Common Stock [Member] Restricted Share Plan [Member]	Dec. 31, 2012 Restricted Common Stock [Member] Restricted Share Plan [Member]	Mar. 31, 2013 Restricted Common Stock [Member] Director Stock Plan [Member]	Dec. 31, 2012 Restricted Common Stock [Member] Director Stock Plan [Member]	Mar. 31, 2013 Restricted Unvested Common Stock [Member] Restricted Share Plan [Member]	Dec. 31, 2012 Restricted Unvested Common Stock [Member] Restricted Share Plan [Member]	Mar. 31, 2013 Restricted Unvested Common Stock [Member] Director Stock Plan [Member]	Dec. 31, 2012 Restricted Unvested Common Stock [Member] Director Stock Plan [Member]	Feb. 28, 2013 Performance Shares [Member] Outperformance Plan [Member]	Dec. 15, 2015 Performance Shares [Member] Outperformance Plan [Member]	Mar. 31, 2013 Performance Shares [Member] Outperformance Plan [Member]	Feb. 28, 2013 Excess Return, Above Threshold [Member] Absolute Component [Member] Performance Shares [Member] Outperformance Plan [Member]	Feb. 28, 2013 Excess Return, Above Threshold [Member] Absolute Component [Member] Performance Shares [Member] Outperformance Plan [Member] Maximum [Member]	Feb. 28, 2013 Excess Return, Above Peer Group [Member] Relative Component [Member] Performance Shares [Member] Outperformance Plan [Member]	Feb. 28, 2013 Cumulative Return, Above Threshold [Member] Relative Component [Member] Performance Shares [Member] Outperformance Plan [Member]	Feb. 28, 2013 Cumulative Return, Above Threshold [Member] Relative Component [Member] Performance Shares [Member] Outperformance Plan [Member] Maximum [Member]	Feb. 28, 2013 Cumulative Return, Above Threshold [Member] Relative Component [Member] Performance Shares [Member] Outperformance Plan [Member] Minimum [Member]	Feb. 28, 2013 Cumulative Return, Above Threshold [Member] Relative Component, Linear Interpolation [Member] Performance Shares [Member] Outperformance Plan [Member] Maximum [Member]	Feb. 28, 2013 Cumulative Return, Equal to Threshold [Member] Relative Component [Member] Performance Shares [Member] Outperformance Plan [Member]	Feb. 28, 2013 Cumulative Return, Equal to Threshold [Member] Relative Component, Linear Interpolation [Member] Performance Shares [Member] Outperformance Plan [Member] Minimum [Member]	Feb. 28, 2013 Cumulative Return, Below Threshold [Member] Relative Component [Member] Performance Shares [Member] Outperformance Plan [Member]	Feb. 28, 2013 Equity Market Capitalization [Member] Performance Shares [Member] Outperformance Plan [Member]	Feb. 28, 2013 Equity Market Capitalization [Member] Performance Shares [Member] Outperformance Plan [Member] Maximum [Member]	Feb. 28, 2013 Stockholder's Book Equity [Member] Performance Shares [Member]	Jan. 30, 2018 OP Units [Member] Outperformance Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Shares Awarded as a Percentage of Maximum																													100.00%				50.00%		0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Return Percentage Threshold																										0.00%	21.00%			18.00%	6.00%	6.00%	0.00%	0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized				500,000
Equity-based compensation		$ 876,000	$ 146,000		$ 2,600,000	$ 1,200,000	$ 2,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Market Capitalization Threshold																										4.00%		4.00%								5.00%
Equity Capitalization, Including Portion Attributable to Noncontrolling Interest, Aggregate Gross Capitalization																																						2,100,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Shares Authorized, Percentage of Benchmark, Potential Share Commitment																																					3.00%
Share-based Compensation Arrangement by Share-based Payment Award, Shares Allocated as a Percentage of Shares Authorized																									100.00%
Percentage of Shares Allowable to be Converted, Percentage																																							33.30%
Share-based Compensation Arrangement by Share-based Payment Award, Shares Authorized, Percentage of Benchmark, Shares Committed Annually																																					1.25%
Share-based Compensation Arrangement by Share-based Payment Award, Periodic Vesting Percentage														20.00%
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number													6,000		584,909	259,909	36,300	30,300	325,000	186,403		27,930
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price															$ 0.00	$ 11.84	$ 0.00	$ 10.68	$ 13.83	$ 11.62	$ 13.23	$ 10.58
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price	$ 10.00
Shares issued in lieu of cash for services, in shares											167,400
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Automatic Grant												3,000
Restricted share vesting period													5 years
Maximum authorized amount as a percentage of shares authorized									10.00%
Number of shares authorized, in shares														99,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period										325,000							6,000		325,000		6,000		8,241,101
Share-based Compensation Arrangement by Share-based Payment Award, Performance Period																								3 years
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price															$ 13.83				$ 13.83		$ 13.23
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period															0		0		0		0
Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price															$ 0.00		$ 0.00		$ 0.00		$ 0.00
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period																			(186,403)		(27,930)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value																			$ (11.62)		$ (10.58)
Allocated Share-based Compensation Expense		$ 3,255,000	$ 146,000					$ 600,000