DEBT - MetaBank and other Mortgage Loans (Details) - Non-recourse loan - MetaBank - Secured debt	Jun. 30, 2017 USD ($) hotel
Debt Instrument [Line Items]
Debt instrument, face amount \| $	$ 47,600,000
Stated interest rate	4.44%
Debt instrument, amortization period after interest only payments period (in years)	25 years
Number of properties that served as collateral for loans \| hotel	3

Debt Instrument, Amortization Period After Interest Only Payments Period

No definition available.

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Namespace Prefix:	inn_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of real estate properties pledged to secure a debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	inn_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- 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

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types: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

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

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- Details

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Namespace Prefix:
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- Details

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