Repurchase Agreements - Summary of Repurchase Agreements (Parenthetical) (Detail) - Bond	Mar. 31, 2019	Dec. 31, 2018
Barclays MRA [Member]
Debt Instrument [Line Items]
Number of corporate bond	1	1

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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