XML 68 R51.htm IDEA: XBRL DOCUMENT v3.10.0.1

Indebtedness - Schedule of Outstanding Debts (Details) - USD ($)	Dec. 31, 2018	Feb. 28, 2018	Dec. 31, 2017	Feb. 29, 2016
Debt Instrument [Line Items]
Face Amount	$ 2,250,000,000		$ 1,750,000,000
Unamortized Discount	$ 9,974,000		3,159,000
Senior unsecured notes due 2019
Debt Instrument [Line Items]
Coupon	3.25%
Face Amount	$ 400,000,000		400,000,000
Unamortized Discount	$ 19,000		78,000
Senior unsecured notes due 2020
Debt Instrument [Line Items]
Coupon	6.75%
Face Amount	$ 200,000,000		200,000,000
Unamortized Discount	$ 274,000		488,000
Unsecured senior notes due 2021
Debt Instrument [Line Items]
Coupon	6.75%
Face Amount	$ 300,000,000		300,000,000
Unamortized Discount	$ 1,558,000		2,093,000
Senior unsecured notes due 2024
Debt Instrument [Line Items]
Coupon	4.75%
Face Amount	$ 250,000,000		250,000,000
Unamortized Discount	$ 421,000		500,000
Senior Unsecured Notes Due 2028
Debt Instrument [Line Items]
Coupon	4.75%	4.75%
Face Amount	$ 500,000,000	$ 500,000,000	0
Unamortized Discount	$ 7,702,000		0
Senior unsecured notes due in 2042
Debt Instrument [Line Items]
Coupon	5.625%
Face Amount	$ 350,000,000		350,000,000
Unamortized Discount	$ 0		0
Senior unsecured notes due in 2046
Debt Instrument [Line Items]
Coupon	6.25%			6.25%
Face Amount	$ 250,000,000		250,000,000	$ 250,000,000
Unamortized Discount	$ 0		$ 0

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

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

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

- Details

Name:	us-gaap_DebtInstrumentAxis=snh_SeniorUnsecuredNotes3.25PercentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=snh_SeniorUnsecuredNotes6.75PercentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=snh_SeniorUnsecuredNotes6.75PercentDue2021Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=snh_SeniorUnsecuredNotes4.75PercentDue2024Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=snh_SeniorUnsecuredNotes4.75PercentDue2028Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=snh_SeniorUnsecuredNotes5.625PercentDue2042Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=snh_SeniorUnsecuredNotes6.25DueIn2046Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: