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Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Jun. 30, 2018	Sep. 30, 2018
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value	$ 1,400,000
Citigroup Global Markets Inc [Member]
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value		$ 285,000
Other Party [Domain]
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value		2,550
Goldman Sachs [Member]
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value		272,000
Proceeds from Legal Settlements		$ 26,721
Military Housing [Domain]
Loss Contingencies [Line Items]
Payments for Legal Settlements	$ 20,413

X

- Definition

The amount or range of possible amounts of gain that could be realized upon the resolution of a contingency.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 30
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6397426&loc=d3e17499-108355

+ Details

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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

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X

- Definition

The amount of cash paid for the settlement of litigation or for other legal issues during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

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- Definition

Cash received for the settlement of litigation during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

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