Reclassifications of Accumulated Other Comprehensive Income (Parenthetical) (Detail) - USD ($) $ in Thousands		3 Months Ended
Mar. 15, 2018	Mar. 31, 2018	Mar. 31, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net realized capital gains		$ 44,505	$ 59,651
Ares \| Insurance Segment
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net realized capital gains	$ 45,700	$ 45,700

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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