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.

No definition available.

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- Definition

Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

+ References

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Fair Value of Financial Instruments - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Gross transfers out of Level 3	$ 3.1	$ 13.9	$ 17.8	$ 14.9
Gross transfers into Level 3		$ 1.3		16.0
Foreign corporate bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Gross transfers out of Level 3			3.3	1.6
Gross transfers into Level 3				14.7
U.S. corporate bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Gross transfers out of Level 3				1.0
Gross transfers into Level 3				1.3
Other asset-backed securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Gross transfers out of Level 3			$ 14.5	$ 12.1