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Commitments and Contingencies - Narrative (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018
Real Estate Properties [Line Items] |  |
General liability insurance limit | $ 200,000,000.0 |
Property and rental value insurance coverage limit | 2,000,000,000.0 |
Terrorist acts insurance coverage limit | 2,000,000,000.0 |
Purchase obligation | 196,900,000 |
Environmental liabilities | 17,898,000 | $ 17,898,000
Additional capital funding committed amount | 57,700,000 |
Consolidated Properties |  |
Real Estate Properties [Line Items] |  |
Purchase obligation | 160,100,000 |
Principal payment guarantees | 8,300,000 |
Unconsolidated Properties |  |
Real Estate Properties [Line Items] |  |
Purchase obligation | $ 36,800,000 |
Minimum |  |
Real Estate Properties [Line Items] |  |
Commitment amortization period | 2 years |
Maximum |  |
Real Estate Properties [Line Items] |  |
Commitment amortization period | 3 years |

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- Definition General Liability Insurance Coverage Limit, Per Occurrence + References No definition available. + Details
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- Definition Property and Rental Value Insurance Coverage Limit + References No definition available. + Details
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- Definition Terrorist Acts Insurance Coverage Limit, Per Occurrence + References No definition available. + Details
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- Definition Total costs accrued as of the balance sheet date for environmental loss contingencies. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 + Details
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- Definition Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12069-110248 + Details
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- Definition Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions. + References No definition available. + Details
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- Definition Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier. + References No definition available. + Details
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- 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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