Revenues from Contracts with Customers - Schedule of Revenues from Contracts with Customers and Our Other Sources of Revenues (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue
Revenues from contracts with customers:	$ 305,342	$ 462,092	$ 977,409	$ 1,299,053
Revenues	435,924	586,634	1,303,572	1,585,768
Gains from mortgage banking activities/originations, net
Disaggregation of Revenue
Other sources of revenue:	91,192	72,332	210,686	148,769
Servicing fees and other
Disaggregation of Revenue
Other sources of revenue:	39,390	52,210	115,477	137,946
Leasing and other commissions
Disaggregation of Revenue
Revenues from contracts with customers:	114,947	213,242	375,465	603,094
Revenues	114,947	213,242	375,465	603,094
Capital markets commissions
Disaggregation of Revenue
Revenues from contracts with customers:	82,956	144,666	263,838	376,213
Management services
Disaggregation of Revenue
Revenues from contracts with customers:	$ 107,439	$ 104,184	$ 338,106	$ 319,746

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Amount, excluding 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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
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Amount of revenue that is not accounted for under Topic 606.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(1))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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