Insurance Operations - Summary of Combined Net Income (Loss) for UPCIC and APPCIC (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Insurance [Abstract]
Combined net income (loss)	$ (3,234)	$ 7,623

Amount of net income for the period determined using accounting principles prescribed or permitted by insurance regulators.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(c))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration