Note Debt Securities Available for Sale (Debt securities available- for-sale - Additional Information) (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale
Gross Unrealized Losses	$ 127,744	$ 209,307

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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