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Sum of all assets excluding the Company's Total Portfolio Assets.

No definition available.

Name:	star_CashAndOtherAssets
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This element represents the aggregate of the holding and operating costs related to real estate held for investment and the net costs related to other real estate owned.

No definition available.

Name:	star_CostOfRealEstateHeldForSaleAndOtherRealEstateOwned
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Costs of Land Sales

No definition available.

Name:	star_CostsofLandSales
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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production including amounts presented in discontinued operations.

No definition available.

Name:	star_DepreciationAndAmortizationIncludingDiscontinuedOperations
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The aggregate total of expenses of managing and administering the affairs of the entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line, excluding stock-based compensation expense.

No definition available.

Name:	star_GeneralAndAdministrativeExpenseExcludingStockBasedCompensationExpense
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The cost of borrowed funds accounted for as interest that was charged against earnings during the period including amounts presented in discontinued operations.

No definition available.

Name:	star_InterestExpenseIncludingDiscontinuedOperations
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Amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date, net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among myriad other features and characteristics. In addition, amount also includes total debt and equity financial instruments including: securities held-to-maturity and securities available-for-sale.

No definition available.

Name:	star_LoansAndOtherLendingInvestments
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Data Type:	xbrli:monetaryItemType
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The aggregate of Total real estate, loans receivable, net and Other investments.

No definition available.

Name:	star_PortfolioAssets
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Carrying amount as of the balance sheet date of costs that were capitalized after acquisition, including property improvements and carrying costs (for example, real estate taxes and insurance), but excluding the initial purchase price.

No definition available.

Name:	star_RealEstateAndAccumulatedDepreciationCostsCapitalizedSubsequentToAcquisition
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Data Type:	xbrli:monetaryItemType
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Carrying amount as of the balance sheet date of investments in land and buildings held for sale, including real estate considered to be inventory of the entity.

No definition available.

Name:	star_RealEstateAvailableAndHeldForSale
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Real Estate Investment Property, Held for Use, Net

No definition available.

Name:	star_RealEstateInvestmentPropertyHeldForUseNet
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Data Type:	xbrli:monetaryItemType
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The sum of the Company's total revenue and other earnings related to the Company's business segments.

No definition available.

Name:	star_RevenueAndOtherEarnings
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Amount of profit or loss during the period recognized by the reportable segment.

No definition available.

Name:	star_SegmentProfitLoss
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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-Section S99

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-Name Staff Accounting Bulletin (SAB)

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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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The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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-Topic 230

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Interest and fee income related to commercial loans including industrial and agricultural, real estate (commercial and residential, construction and development), trade financing, and lease financing.

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Revenue from the sale of land in the reporting period.

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-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(e))

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Name:	us-gaap_LandSales
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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

No definition available.

Name:	us-gaap_NumberOfReportableSegments
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Balance Type:	na
Period Type:	duration

The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 25

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This element represents a sum total of expenses not separately reflected on the income statement for the period.

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-Name Accounting Standards Codification

-Topic 944

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Reflects the sum of all other revenue and income recognized by the entity in the period not otherwise specified in the income statement.

Name:	us-gaap_OtherIncome
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Other investments not otherwise specified in the taxonomy.

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-Name Accounting Standards Codification

-Topic 210

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-Section S99

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-Topic 944

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-Subparagraph (SX 210.7-03.1(f,g))

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Name:	us-gaap_OtherInvestments
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Period Type:	instant

Amount of expense related to loss from loan transactions.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.11)

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Name:	us-gaap_ProvisionForLoanLossesExpensed
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Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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-Name Accounting Standards Codification

-Topic 944

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(d))

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