Recently Issued Accounting Standards - Additional Information (Detail) - New Accounting Pronouncement, Early Adoption, Effect [Member] $ in Millions	Jan. 01, 2018 USD ($)
Accumulated other comprehensive income (loss)
New Accounting Pronouncement, Early Adoption [Line Items]
Tax cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings	$ 7
Retained earnings
New Accounting Pronouncement, Early Adoption [Line Items]
Tax cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings	$ 7

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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