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Compensation Plans - Expense Recognition of Deferred Compensation (Detail) - Restricted Stock Units (RSUs)	Mar. 31, 2019 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
2019 (Remaining Period)	$ 5,501,114
2020	6,146,135
2021	4,865,576
2022	3,878,442
2023	1,641,414
Thereafter	1,624,093
Total	$ 23,656,774

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Unrecognized cost of unvested share-based compensation awards.

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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=109197908&loc=d3e5070-113901

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