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v3.19.3

Commitments and Contingencies (Details) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2019 USD ($) property | Dec. 31, 2018 USD ($) property | Dec. 31, 2017 USD ($)
Purchase Commitment [Line Items] |  |  |
Single-family properties sales in escrow | property | 288 | 78 |
Single-family properties sales in escrow, selling price | $ 51.9 | $ 13.6 |
Silver Bay Realty Trust Corp. |  |  |
Gain (Loss) on Sale of Securities, Net [Abstract] |  |  |
Gain (loss) on sale of equity investments |  |  | $ 3.0
Single Family Properties |  |  |
Purchase Commitment [Line Items] |  |  |
Purchase price of commitment to acquire single-family properties | 3.5 | 25.3 |
Land |  |  |
Purchase Commitment [Line Items] |  |  |
Purchase price of commitment to acquire single-family properties | $ 65.3 | $ 58.1 |
Commitment To Acquire Properties |  |  |
Purchase Commitment [Line Items] |  |  |
Number of properties | property | 13 | 88 |
Surety bond |  |  |
Purchase Commitment [Line Items] |  |  |
Surety bonds related to development contracts | $ 9.9 | $ 5.1 |

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- Definition The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees. + 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 (c) -URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248 + Details
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