Amount Exceeding Carrying Value Of Assets Under Leases

No definition available.

Name:	bkd_AmountExceedingCarryingValueOfAssetsUnderLeases
Namespace Prefix:	bkd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Assets Under Leases

+ References

No definition available.

+ Details

Name:	bkd_AssetsUnderLeases
Namespace Prefix:	bkd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Disposal Group, Number Of Communities Disposed Of

+ References

No definition available.

+ Details

Name:	bkd_DisposalGroupNumberOfCommunitiesDisposedOf
Namespace Prefix:	bkd_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Equity Method Investments, Number Of Communities Managed

+ References

No definition available.

+ Details

Name:	bkd_EquityMethodInvestmentsNumberOfCommunitiesManaged
Namespace Prefix:	bkd_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Increase (Decrease) In Lease Liabilities

+ References

No definition available.

+ Details

Name:	bkd_IncreaseDecreaseInLeaseLiabilities
Namespace Prefix:	bkd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Increase (Decrease) In Long Term Debt And Capital Lease Obligations

+ References

No definition available.

+ Details

Name:	bkd_IncreaseDecreaseInLongTermDebtAndCapitalLeaseObligations
Namespace Prefix:	bkd_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number Of Communities Acquired

+ References

No definition available.

+ Details

Name:	bkd_NumberOfCommunitiesAcquired
Namespace Prefix:	bkd_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number Of Communities, Management Retained

+ References

No definition available.

+ Details

Name:	bkd_NumberOfCommunitiesManagementRetained
Namespace Prefix:	bkd_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number Of Communities Previously Subject To Sale Leaseback Transactions

+ References

No definition available.

+ Details

Name:	bkd_NumberOfCommunitiesPreviouslySubjectToSaleLeasebackTransactions
Namespace Prefix:	bkd_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number Of Joint Ventures

+ References

No definition available.

+ Details

Name:	bkd_NumberOfJointVentures
Namespace Prefix:	bkd_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Numbers Of Communities With Rent Reduction

+ References

No definition available.

+ Details

Name:	bkd_NumbersOfCommunitiesWithRentReduction
Namespace Prefix:	bkd_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Operating Lease, Annual Rent Reduction

+ References

No definition available.

+ Details

Name:	bkd_OperatingLeaseAnnualRentReduction
Namespace Prefix:	bkd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Operating Leases, Number Of Communities

+ References

No definition available.

+ Details

Name:	bkd_OperatingLeasesNumberOfCommunities
Namespace Prefix:	bkd_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Payment To Acquire Leased Assets

+ References

No definition available.

+ Details

Name:	bkd_PaymentToAcquireLeasedAssets
Namespace Prefix:	bkd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Payments to Acquire Asset From Joint Venture

+ References

No definition available.

+ Details

Name:	bkd_PaymentstoAcquireAssetFromJointVenture
Namespace Prefix:	bkd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

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

- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84164817&loc=d3e45280-112737

Reference 3: 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=6879938&loc=d3e572229-122910

+ Details

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

- Definition

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(a),(d))
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

+ Details

Name:	us-gaap_CostOfGoodsAndServicesSold
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

+ Details

Name:	us-gaap_GainLossOnContractTermination
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

+ Details

Name:	us-gaap_GainLossOnDispositionOfAssets1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of gain (loss) on termination of lease before expiration of lease term.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 40
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=77888415&loc=SL77918607-209975

+ Details

Name:	us-gaap_GainLossOnTerminationOfLease
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The increase (decrease) during the reporting period, excluding the portion taken into income, in the liability reflecting revenue yet to be earned for which cash or other forms of consideration was received or recorded as a receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

+ Details

Name:	us-gaap_IncreaseDecreaseInDeferredRevenue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Cash payments to lessor's for use of assets under operating leases.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3536-108585

+ Details

Name:	us-gaap_PaymentsForRent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow from the sale of an investment interest in a joint venture that the reporting entity has not previously accounted for using consolidation or the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585

+ Details

Name:	us-gaap_ProceedsFromDivestitureOfInterestInJointVenture
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130539-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130545-203045

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130543-203045

+ Details

Name:	us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	bkd_ByTransactionNameAxis=bkd_MasterLeaseTransactionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	bkd_ByTransactionNameAxis=bkd_RIDEAVenturesRestructuringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=bkd_HCPInc.Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=us-gaap_ScenarioForecastMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=bkd_VariableInterestEntityNotPrimaryBeneficiaryRealEstateCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=bkd_A16CommunitiesDisposedOfThroughLeaseTerminationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=bkd_A17CommunitiesDisposedOfThroughLeaseTerminationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=bkd_A37CommunitiesDisposedOfThroughManagementTerminationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=bkd_A17CommunitiesDisposedOfThroughManagementTerminationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=bkd_A33CommunitiesDisposedOfThroughLeaseTerminationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=bkd_RetirementCentersMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=bkd_AssistedLivingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=bkd_CcrcsRentalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=us-gaap_HealthCareResidentServiceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=us-gaap_RealEstateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ProductOrServiceAxis=us-gaap_ManagementServiceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Acquisitions, Dispositions and Other Significant Transactions - HCP Master Lease Transaction and RIDEA Ventures Restructuring (Details) $ in Thousands					1 Months Ended				3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 01, 2018 community	Jan. 01, 2018 USD ($) community	Nov. 02, 2017 community	Nov. 01, 2017 community joint_venture	Apr. 30, 2018 USD ($) community	Mar. 31, 2018 USD ($)	Jan. 31, 2018 USD ($) community	Dec. 31, 2017 USD ($) community	Sep. 30, 2018 USD ($) community	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) community	Sep. 30, 2017 USD ($)	Dec. 31, 2018 community	Dec. 31, 2017 USD ($)
Business Acquisition [Line Items]
Deferred revenue											$ 3,898	$ (1,513)
Non-cash management contract termination fee											5,649	0
Gain (loss) on sale of assets, net									$ 9,833	$ (233)	76,586	(1,383)
Gain on facility lease termination									(2,337)	(4,938)	(148,804)	(11,306)
Revenue									840,179		2,642,414
Cash lease payments									73,969	90,303	250,677	275,506
Master Lease Transactions
Business Acquisition [Line Items]
Annual rent reduction		$ 2,500
Number of communities with rent reduction \| community		2
RIDEA Ventures Restructuring
Business Acquisition [Line Items]
Number of communities management is retained \| community					18
Reduction in lease liabilities											9,700
Deferred revenue											$ 9,700
HCP, Inc. \| Master Lease Transactions
Business Acquisition [Line Items]
Number of communities acquired \| community											2
Payment to acquire leased assets											$ 35,400
Number of communities leased \| community			43
HCP, Inc. \| RIDEA Ventures Restructuring
Business Acquisition [Line Items]
Number of communities acquired \| community					3		1
Payments to acquire asset from joint venture					$ 207,400		$ 32,100
Forecast \| Master Lease Transactions
Business Acquisition [Line Items]
Number of communities disposed of \| community													33
RIDEA Ventures \| RIDEA Ventures Restructuring
Business Acquisition [Line Items]
Percentage ownership						10.00%		10.00%						10.00%
Number of joint ventures				2				1
Proceeds from sale of joint venture interest						$ 62,300		$ 32,100
Number of communities managed \| community				59
Gain (loss) on sale of assets, net						$ 41,700		$ 7,200
16 Communities Disposed Of Through Lease Terminations \| HCP, Inc. \| Master Lease Transactions
Business Acquisition [Line Items]
Number of communities disposed of \| community											16
Capital Lease Obligations									160,800		$ 160,800
Gain (loss) on sale of assets, net									6,100		12,600
Gain on facility lease termination											1,800
Assets under leases									147,800		$ 147,800
Number of communities previously subject to sale leaseback transactions \| community											6
17 Communities Disposed Of Through Lease Terminations
Business Acquisition [Line Items]
Capital Lease Obligations									217,900		$ 217,900
Assets under leases									185,100		185,100
Amount exceeding carrying value of assets under leases									32,800		$ 32,800
Number of communities previously subject to sale leaseback transactions \| community											14
Cash lease payments									$ 4,900	5,400	$ 14,600	16,100
37 Communities Disposed Of Through Management Termination \| RIDEA Ventures Restructuring
Business Acquisition [Line Items]
Number of communities disposed of \| community			37						3		20
Non-cash management contract termination fee									$ 600		$ 5,600
17 Communities Disposed Of Through Management Termination \| Forecast \| RIDEA Ventures Restructuring
Business Acquisition [Line Items]
Number of communities disposed of \| community													17
33 Communities Disposed Of Through Lease Terminations
Business Acquisition [Line Items]
Reduction in capital lease obligations and assets under lease														$ 145,600
Retirement Centers
Business Acquisition [Line Items]
Revenue									144,631		$ 462,321
Retirement Centers \| 17 Communities Disposed Of Through Lease Terminations
Business Acquisition [Line Items]
Number of communities disposed of \| community											3
Assisted Living
Business Acquisition [Line Items]
Revenue									483,125		$ 1,537,432
Assisted Living \| 17 Communities Disposed Of Through Lease Terminations
Business Acquisition [Line Items]
Number of communities disposed of \| community											13
CCRCs Rental
Business Acquisition [Line Items]
Revenue									104,147		$ 314,012
CCRCs Rental \| 17 Communities Disposed Of Through Lease Terminations
Business Acquisition [Line Items]
Number of communities disposed of \| community											1
Resident fees
Business Acquisition [Line Items]
Revenue									840,179	922,892	$ 2,642,414	2,873,889
Resident fees \| 17 Communities Disposed Of Through Lease Terminations
Business Acquisition [Line Items]
Revenue									14,800	15,100	44,700	46,000
Facility operating expense
Business Acquisition [Line Items]
Costs of services									607,076	650,654	1,866,477	1,967,601
Facility operating expense \| 17 Communities Disposed Of Through Lease Terminations
Business Acquisition [Line Items]
Costs of services									10,700	10,600	32,100	30,700
Management fees
Business Acquisition [Line Items]
Revenue									18,528	18,138	54,280	56,474
Management fees \| 17 Communities Disposed Of Through Management Termination
Business Acquisition [Line Items]
Revenue									$ 1,200	$ 1,100	$ 3,500	$ 3,500
Subsequent event \| 17 Communities Disposed Of Through Lease Terminations \| HCP, Inc. \| Master Lease Transactions
Business Acquisition [Line Items]
Number of communities disposed of \| community	17