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Statement of Accounting Policies - Additional Information (Detail) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2016 USD ($) county Segment | Dec. 31, 2015 USD ($)
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 | $ 3,300,000 |
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 |  | $ 3,700,000

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