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Compensation Plans - Expense Recognition of Deferred Compensation (Detail) - Restricted stock	Jun. 30, 2019 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2019 (Remaining Period)	$ 3,639,099
2020	6,169,469
2021	4,888,910
2022	3,906,761
2023	1,674,718
Thereafter	1,640,745
Total	$ 21,919,702

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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