Segment Information and Revenue - Depreciation and Amortization Expense and Share-based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting, Revenue Reconciling Item [Line Items]
Depreciation and amortization			$ 81,977	$ 63,888
Share-based compensation expense			145,105	151,884
Homes
Segment Reporting, Revenue Reconciling Item [Line Items]
Depreciation and amortization	$ 3,029	$ 2,331	9,201	5,384
Share-based compensation expense	11,815	8,025	35,847	20,666
IMT
Segment Reporting, Revenue Reconciling Item [Line Items]
Depreciation and amortization	22,074	18,362	67,889	54,264
Share-based compensation expense	33,435	30,687	98,940	118,101
Mortgages Segment
Segment Reporting, Revenue Reconciling Item [Line Items]
Depreciation and amortization	1,675	1,467	4,887	4,240
Share-based compensation expense	$ 3,709	$ 3,416	$ 10,318	$ 13,117

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

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Amount of noncash expense for share-based payment arrangement.

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-Topic 230
-SubTopic 10
-Section 45
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