XML 87 R88.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Debt Obligations, net (Schedule of Debt) (Details) - USD ($) | 1 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Dec. 31, 2019 | Oct. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Nov. 30, 2019 | Oct. 31, 2017 | Sep. 30, 2017
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total debt obligations | $ 3,436,038,000 |  |  |  |  | $ 3,436,038,000 | $ 3,661,617,000 |  |  |  |
Debt discounts and deferred financing costs, net | (48,958,000) |  |  |  |  | (48,958,000) | (52,531,000) |  |  |  |
Total debt obligations, net | $ 3,387,080,000 |  |  |  |  | 3,387,080,000 | 3,609,086,000 |  |  |  |
Payment for debt extinguishment or debt prepayment cost |  |  |  |  |  | 20,606,000 | 4,132,000 | $ 14,108,000 |  |  |
Interest costs capitalized |  |  |  |  |  | $ 7,500,000 | 11,300,000 | $ 8,500,000 |  |  |
Senior Term Loan | LIBOR |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basis point spread on variable interest rate (percent) |  |  |  |  |  | 1.00% |  |  |  |  |
5.00% senior notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stated interest rate (percent) | 5.00% |  |  |  |  | 5.00% |  |  |  |  |
4.625% senior notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Payment for debt extinguishment or debt prepayment cost |  | $ 6,000,000.0 |  |  |  |  |  |  |  |  |
Stated interest rate (percent) | 4.625% |  |  |  |  | 4.625% |  |  |  |  |
6.50% senior notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Payment for debt extinguishment or debt prepayment cost |  | $ 4,500,000 |  |  |  |  |  |  |  |  |
Stated interest rate (percent) | 6.50% |  |  |  |  | 6.50% |  |  |  |  |
6.00% senior notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Payment for debt extinguishment or debt prepayment cost | $ 10,100,000 |  |  |  |  |  |  |  |  |  |
Stated interest rate (percent) | 6.00% |  |  |  |  | 6.00% |  |  |  |  |
5.25% senior notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stated interest rate (percent) | 5.25% |  |  |  |  | 5.25% |  |  |  |  |
3.125% senior convertible notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stated interest rate (percent) | 3.125% |  |  |  |  | 3.125% |  | 3.125% |  |  |
Unsecured 4.75 Senior Notes Due October 2024 |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stated interest rate (percent) | 4.75% |  |  |  |  | 4.75% |  |  |  |  |
4.25% senior notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stated interest rate (percent) | 4.25% |  |  |  |  | 4.25% |  |  |  |  |
Secured credit facilities and mortgages |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total debt obligations | $ 1,212,993,000 |  |  |  |  | $ 1,212,993,000 | 1,449,117,000 |  |  |  |
Debt discounts and deferred financing costs, net | (7,730,000) |  |  |  |  | (7,730,000) |  |  |  |  |
Total debt obligations, net | 1,205,263,000 |  |  |  |  | 1,205,263,000 |  |  |  |  |
Secured credit facilities and mortgages | 2015 $350 Million Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total debt obligations | 0 |  |  |  |  | 0 | 0 |  |  |  |
Debt instrument, face amount | 350,000,000 |  |  |  |  | $ 350,000,000 |  |  |  |  |
Secured credit facilities and mortgages | 2015 $350 Million Revolving Credit Facility | LIBOR |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basis point spread on variable interest rate (percent) |  |  |  |  |  | 2.25% |  |  |  |  |
Debt instrument term |  |  |  |  |  | 1 year |  |  |  |  |
Secured credit facilities and mortgages | 2015 $350 Million Revolving Credit Facility | LIBOR | Minimum |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basis point spread on variable interest rate (percent) |  |  | 2.00% |  |  | 1.00% |  |  |  |  |
Secured credit facilities and mortgages | 2015 $350 Million Revolving Credit Facility | LIBOR | Minimum | Interest Rate Category Two |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basis point spread on variable interest rate (percent) |  |  |  |  |  | 2.00% |  |  |  |  |
Secured credit facilities and mortgages | 2015 $350 Million Revolving Credit Facility | LIBOR | Maximum |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basis point spread on variable interest rate (percent) |  |  | 2.50% |  |  |  |  |  |  |  |
Secured credit facilities and mortgages | 2015 $350 Million Revolving Credit Facility | LIBOR | Maximum | Interest Rate Category Two |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basis point spread on variable interest rate (percent) |  |  |  |  |  | 2.50% |  |  |  |  |
Secured credit facilities and mortgages | 2015 $350 Million Revolving Credit Facility | Base Rate | Minimum |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basis point spread on variable interest rate (percent) |  |  | 1.00% |  |  |  |  |  |  |  |
Secured credit facilities and mortgages | 2015 $350 Million Revolving Credit Facility | Base Rate | Minimum | Interest Rate Category One |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basis point spread on variable interest rate (percent) |  |  |  |  |  | 1.00% |  |  |  |  |
Secured credit facilities and mortgages | 2015 $350 Million Revolving Credit Facility | Base Rate | Maximum |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basis point spread on variable interest rate (percent) |  |  | 1.50% |  |  |  |  |  |  |  |
Secured credit facilities and mortgages | 2015 $350 Million Revolving Credit Facility | Base Rate | Maximum | Interest Rate Category One |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basis point spread on variable interest rate (percent) |  |  |  |  |  | 1.50% |  |  |  |  |
Secured credit facilities and mortgages | 2015 $350 Million Revolving Credit Facility | Federal Funds Rate |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basis point spread on variable interest rate (percent) |  |  |  |  |  | 0.50% |  |  |  |  |
Secured credit facilities and mortgages | Senior Term Loan |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total debt obligations | 491,875,000 |  |  |  |  | $ 491,875,000 | 646,750,000 |  |  |  |
Debt instrument, face amount |  |  |  |  | $ 650,000,000.0 |  |  |  |  |  |
Secured credit facilities and mortgages | Senior Term Loan | LIBOR |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basis point spread on variable interest rate (percent) |  |  |  |  | 2.75% | 2.75% |  |  |  |  |
Secured credit facilities and mortgages | Senior Term Loan | LIBOR | Maximum |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basis point spread on variable interest rate (percent) |  |  |  |  |  | 1.75% |  |  |  |  |
Secured credit facilities and mortgages | Senior Term Loan | Federal Funds Rate |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basis point spread on variable interest rate (percent) |  |  |  |  |  | 0.50% |  |  |  |  |
Secured credit facilities and mortgages | Mortgages collateralized by net lease assets |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total debt obligations | $ 721,118,000 |  |  |  |  | $ 721,118,000 | 802,367,000 |  |  |  |
Weighted average interest rate (percent) | 4.37% |  |  |  |  | 4.37% |  |  |  |  |
Secured credit facilities and mortgages | Mortgages collateralized by net lease assets | Minimum |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stated interest rate (percent) | 3.31% |  |  |  |  | 3.31% |  |  |  |  |
Secured credit facilities and mortgages | Mortgages collateralized by net lease assets | Maximum |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stated interest rate (percent) | 7.26% |  |  |  |  | 7.26% |  |  |  |  |
Unsecured notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total debt obligations | $ 2,123,045,000 |  |  |  |  | $ 2,123,045,000 | 2,112,500,000 |  |  |  |
Unsecured notes | 5.00% senior notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total debt obligations | 0 |  |  |  |  | 0 | 375,000,000 |  |  |  |
Unsecured notes | 4.625% senior notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total debt obligations | 0 |  |  |  |  | 0 | 400,000,000 |  |  |  |
Stated interest rate (percent) |  |  | 4.625% |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  | $ 400,000,000.0 |  |  |  |  |  |  |  |
Unsecured notes | 6.50% senior notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total debt obligations | 0 |  |  |  |  | 0 | 275,000,000 |  |  |  |
Stated interest rate (percent) |  |  | 6.50% |  |  |  |  |  |  |  |
Debt instrument, face amount |  |  | $ 275,000,000.0 |  |  |  |  |  |  |  |
Unsecured notes | 6.00% senior notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total debt obligations | $ 110,545,000 |  |  |  |  | $ 110,545,000 | 375,000,000 |  |  |  |
Stated interest rate (percent) | 6.00% |  |  |  |  | 6.00% |  |  |  |  |
Unsecured notes | 5.25% senior notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total debt obligations | $ 400,000,000 |  |  |  |  | $ 400,000,000 | 400,000,000 |  |  |  |
Unsecured notes | 3.125% senior convertible notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total debt obligations | 287,500,000 |  |  |  |  | 287,500,000 | 287,500,000 |  |  |  |
Total debt obligations, net | $ 268,700,000 |  |  |  |  | $ 268,700,000 | $ 262,600,000 |  |  |  |
Stated interest rate (percent) | 3.125% |  |  |  |  | 3.125% | 3.125% |  |  |  | 3.125%
Convertible debt conversion ratio (in shares per par value) |  |  |  |  |  | 67.92 |  |  |  |  |
Convertible debt conversion ratio principal amount |  |  |  |  |  | $ 1,000 |  |  |  |  |
Convertible debt conversion price (in dollars per share) | $ 14.72 |  |  |  |  | $ 14.72 |  |  |  |  |
Liability component of convertible debt |  |  |  |  |  |  |  |  |  | $ 34,000,000.0 | $ 221,800,000
Equity component of convertible debt |  |  |  |  |  |  |  |  |  | 3,400,000 | $ 22,500,000
Debt instrument, face amount |  |  |  |  |  |  |  |  |  | $ 37,500,000 |
Unamortized discount | $ 15,500,000 |  |  |  |  | $ 15,500,000 | $ 20,500,000 |  |  |  |
Contractual interest |  |  |  |  |  | 9,000,000.0 | 9,000,000.0 | $ 2,500,000 |  |  |
Amortization of debt discount |  |  |  |  |  | $ 5,000,000.0 | $ 4,700,000 | $ 1,300,000 |  |  |
Effective interest rate (percent) | 5.20% |  |  |  |  | 5.20% | 5.20% | 5.20% |  |  |
Unsecured notes | Unsecured 4.75 Senior Notes Due October 2024 |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total debt obligations | $ 775,000,000 |  |  |  |  | $ 775,000,000 | $ 0 |  |  |  |
Stated interest rate (percent) |  |  | 4.75% |  |  |  |  |  | 4.75% |  |
Debt instrument, face amount |  |  | $ 675,000,000.0 |  |  |  |  |  | $ 100,000,000.0 |  |
Effective interest rate (percent) |  |  |  |  |  |  |  |  | 4.29% |  |
Unsecured notes | 4.25% senior notes |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total debt obligations | $ 550,000,000 |  |  |  |  | $ 550,000,000 | 0 |  |  |  |
Stated interest rate (percent) | 4.25% |  |  |  |  | 4.25% |  |  |  |  |
Debt instrument, face amount | $ 550,000,000.0 |  |  |  |  | $ 550,000,000.0 |  |  |  |  |
Other debt obligations | Trust preferred securities |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total debt obligations | $ 100,000,000 |  |  |  |  | $ 100,000,000 | $ 100,000,000 |  |  |  |
Other debt obligations | Trust preferred securities | LIBOR |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Basis point spread on variable interest rate (percent) |  |  |  |  |  | 1.50% |  |  |  |  |
Net Lease Asset |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Non-recourse debt assumed by buyer |  |  |  | $ 228,000,000.0 |  | $ 228,000,000.0 |  |  |  |  |

X
- Definition Debt Instrument, Convertible, Principal Amount Per Conversion Ratio + References No definition available. + Details
Name: | star_DebtInstrumentConvertiblePrincipalAmountPerConversionRatio
Namespace Prefix: | star_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Sale of Property Nonrecourse Debt Assumed by Other Party + References No definition available. + Details
Name: | star_SaleofPropertyNonrecourseDebtAssumedbyOtherParty
Namespace Prefix: | star_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28541-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.8) -URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227 + Details
Name: | us-gaap_AmortizationOfDebtDiscountPremium
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -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 + Details
Name: | us-gaap_ConvertibleDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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=119400593&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -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 + Details
Name: | us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870 + Details
Name: | us-gaap_DebtInstrumentConvertibleCarryingAmountOfTheEquityComponent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The price per share of the conversion feature embedded in the debt instrument. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031898-161870 + Details
Name: | us-gaap_DebtInstrumentConvertibleConversionPrice1
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21521-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(5)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644 + Details
Name: | us-gaap_DebtInstrumentConvertibleConversionRatio1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | duration

X
- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
Name: | us-gaap_DebtInstrumentFaceAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- 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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -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
Name: | us-gaap_DebtInstrumentInterestRateEffectivePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- 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
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentTerm
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, after accumulated amortization, of debt discount. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28541-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
Name: | us-gaap_DebtInstrumentUnamortizedDiscount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of unamortized debt discount (premium) and debt issuance costs. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399 + Details
Name: | us-gaap_DebtInstrumentUnamortizedDiscountPremiumAndDebtIssuanceCostsNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Weighted average interest rate of debt outstanding. + References No definition available. + Details
Name: | us-gaap_DebtWeightedAverageInterestRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of interest capitalized during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391 + Details
Name: | us-gaap_InterestCostsCapitalized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of the cost of borrowed funds accounted for as interest expense for debt. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.8) -URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227 + Details
Name: | us-gaap_InterestExpenseDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -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 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585 + Details
Name: | us-gaap_PaymentsOfDebtExtinguishmentCosts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_DebtInstrumentAxis=star_A2016SeniorSecuredCreditFacilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=star_UnsecuredNotesFivePercentSeniorNotesDueJuly2019Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=star_Unsecured4.625SeniorNotesDueSeptember2020Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=star_UnsecuredNotesSixPointFivePercentSeniorNotesDueJuly2021Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=star_UnsecuredSixPercentSeniorNotesDueApril2022Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=star_Unsecured5.25SeniorNotesDueSeptember2022Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=star_Unsecured3.125SeniorConvertibleNotesDueSeptember2022Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=star_Unsecured4.75SeniorNotesDueOctober2024Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=star_Unsecured4.25SeniorConvertibleNotesDueAugust2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_SecuredDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=star_SecuredRevolvingCreditFacilityDueSeptember2022Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | star_DebtInstrumentInterestRateCategoryAxis=star_InterestRateCategoryTwoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_BaseRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | star_DebtInstrumentInterestRateCategoryAxis=star_InterestRateCategoryOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_FederalFundsEffectiveSwapRateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=star_SecuredTermLoansCollateralizedByLoansNetLeaseAssetsDueThrough2026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=star_UnsecuredDebtNotesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=star_UnsecuredDebtOtherMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=star_OtherDebtSecuritiesDueOctober2035Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RealEstatePropertiesAxis=star_NetLeaseAssetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |