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Investments - Additional Information (Detail) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Schedule Of Investments [Line Items] |  |  |
Equity method investments | $ 38,600,000 |  | $ 40,000,000.0
Gains (losses) on equity method investments | 1,023,000 | $ 783,000 |
Impairment charge on equity method investments | 2,500,000 | 0 |
Investments | 38,966,000 |  | 40,349,000
Consolidated VIE, total assets | 5,728,159,000 |  | 3,916,120,000
Consolidated VIE, total liabilities | 4,988,746,000 |  | 3,148,745,000
Maximum exposure to loss | 2,100,000 |  | 2,800,000
Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Schedule Of Investments [Line Items] |  |  |
Consolidated VIE, total assets | 6,600,000 |  | 7,400,000
Consolidated VIE, total liabilities | 2,500,000 |  | 2,100,000
Equity Investments [Member] |  |  |
Schedule Of Investments [Line Items] |  |  |
Investments | 400,000 |  | $ 400,000
Gains (losses) on equity method investments | 0 | 0 |
Impairment charges, alternative measurements | 0 | 0 |
Unrealized gains (losses) to reflect observable transactions | $ (40,300) | $ 20,400,000 |

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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(11)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(12)) -URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910 + Details
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