Debt Instrument, Lender Fees, Amount Recorded as a Loss on Early Extinguishment of Debt

No definition available.

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

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 2: 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

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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 210.5-02.22(a)(1))

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

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Details

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- Details

Name:	us-gaap_LongtermDebtTypeAxis=star_February2013SecuredCreditFacilityMember
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- Details

Name:	star_RepaymentTypeAxis=star_EarlyRepaymentMember
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Debt Obligations, net (Unsecured Notes Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 10, 2014
Debt Instrument [Line Items]
Repayments of Debt		$ 247,055	$ 1,408,935
4.00% senior notes
Debt Instrument [Line Items]
Stated Interest Rates		4.00%		4.00%
Debt instrument, face amount				$ 550,000
5.00% senior notes
Debt Instrument [Line Items]
Stated Interest Rates		5.00%		5.00%
Debt instrument, face amount				$ 770,000
February 2013 Secured Credit Facility [Member]
Debt Instrument [Line Items]
Repayments of Debt	$ 1,320,000
Early Repayment [Member] \| February 2013 Secured Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Lender Fees, Amount Recorded as a Loss on Early Extinguishment of Debt	$ 22,800