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Debt instrument, term of variable rate, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

No definition available.

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The percentage of estimated total annualized cost of capital.

No definition available.

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

No definition available.

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

No definition available.

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Indicates type of variable interest rate on debt instrument.

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No definition available.

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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.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Name:	us-gaap_LineOfCreditFacilityAxis=star_FirstFoundationBankMember
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Name:	us-gaap_LineOfCreditFacilityAxis=star_WoodforestNationalBankMember
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Name:	us-gaap_LineOfCreditFacilityAxis=star_PeapackGladstoneBankMember
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