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		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Gross transfers into Level 3	$ 0.0		$ 5.8	$ 0.0
Gross transfers out of Level 3	$ 10.2	$ 0.0	45.6	17.8
U.S. corporate bonds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Gross transfers into Level 3			0.0	0.0
Gross transfers out of Level 3			2.8	0.0
CMBS
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Gross transfers into Level 3			0.0	0.0
Gross transfers out of Level 3			5.8	0.0
Other asset-backed securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Gross transfers into Level 3			5.8	0.0
Gross transfers out of Level 3			$ 37.0	$ 14.5