Line of Credit, Additional Borrowing Capacity Without Restrictions

No definition available.

Name:	inn_LineofCreditAdditionalBorrowingCapacityWithoutRestrictions
Namespace Prefix:	inn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

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+ Details

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

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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

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

- 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.

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+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Details

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- Details

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Balance Type:
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- Details

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Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
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Data Type:	na
Balance Type:
Period Type:

- Details

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- Details

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Balance Type:
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DEBT - Term Loans (Details) - USD ($)	Feb. 15, 2018	Sep. 26, 2017	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Debt, net of debt issuance costs			$ 1,069,797,000	$ 1,094,745,000
2017 Term Loan \| Unsecured debt
Debt Instrument [Line Items]
Debt instrument, face amount		$ 225,000,000.0
Additional borrowing capacity		$ 175,000,000
Effective interest rate			2.70%
Debt, net of debt issuance costs			$ 62,000,000
2017 Term Loan \| Unsecured debt \| Option One \| Minimum \| LIBOR
Debt Instrument [Line Items]
Debt, basis spread on variable rate		1.45%
2017 Term Loan \| Unsecured debt \| Option One \| Maximum \| LIBOR
Debt Instrument [Line Items]
Debt, basis spread on variable rate		2.25%
2018 Term Loan \| Unsecured debt
Debt Instrument [Line Items]
Debt instrument, face amount	$ 225,000,000.0
Additional borrowing capacity	$ 150,000,000
Effective interest rate			2.40%
2018 Term Loan \| Unsecured debt \| Option One \| Minimum \| LIBOR
Debt Instrument [Line Items]
Debt, basis spread on variable rate	1.35%
2018 Term Loan \| Unsecured debt \| Option One \| Maximum \| LIBOR
Debt Instrument [Line Items]
Debt, basis spread on variable rate	1.95%