For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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- Definition

Amount of investment in equity security without readily determinable fair value.

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Amount, after allowance for credit loss, of financing receivable, classified as current. Includes, but is not limited to, notes and loan receivable.

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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.

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Value of investments transferred to the entity's investments in noncash transactions.

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Investments - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2018
Schedule of Investments [Line Items]
Transfer to investments	$ 3.4
Carrying value		$ 3.4
Other Receivables [Member]
Schedule of Investments [Line Items]
Note receivable		$ 0.9	$ 4.3
ASU 2016-01 [Member]
Schedule of Investments [Line Items]
Reclassification of net unrealized gains of marketable equity securities from AOCI to retained earnings				$ 3.2
Investment [Member] \| Issuer Concentration [Member] \| Market Value of Total Investment Portfolio [Member]
Schedule of Investments [Line Items]
Investment concentration risk percentage		5.00%