Statement of Accounting Policies - Additional Information (Detail)	12 Months Ended
Dec. 31, 2018 USD ($) county Segment	Dec. 31, 2017 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of counties in which entity provides services \| county	15
Business segments \| Segment	1
Equity investments	20.00%
Loans past due days	90 days
Excess impaired credits	$ 100,000
Other liabilities	$ 3,800,000
Software purchases and developed are capitalized and amortized on straight-line basis	7 years
Guaranteed Minimum Death Benefit [Member]
Summary Of Significant Accounting Policies [Line Items]
Other liabilities		$ 3,900,000

Amount of accrued obligation to policyholders that relates to insured events for long-duration contracts.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 3
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.7-03.13(a)(1))
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-Publisher FASB
-Name Accounting Standards Codification
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