Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount

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- Definition

Increase (decrease) in the present value of expected future paid losses and expenses that exceeded the present value of expected future premium to be collected and already established loss and loss adjustment expense reserves.

+ References

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- Definition

The number of payments past due in order for such loans to be considered in default.

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- Definition

Postemployment Benefits Liability, Maximum Age For Qualified Employees

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- Definition

Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act of 2017.

+ References

No definition available.

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

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-Name Accounting Standards Codification
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-Topic 850
-SubTopic 10
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-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39622-107864

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Significant Accounting Policies (Details)	3 Months Ended	12 Months Ended
Significant Accounting Policies (Details)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 USD ($) Payment	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Home office and equipment [Abstract]
Accumulated depreciation of home office and equipment	$ 33,900,000	$ 33,900,000	$ 30,600,000	$ 26,100,000
Depreciation expense of home office and equipment		$ 5,400,000	4,600,000	3,200,000
Minimum number of payments past due to be in default \| Payment		2
Decrease in premium deficiency reserve		$ 0	0	23,751,000
Maximum age for qualified employees for both medical and dental benefits		65 years
Related party transaction amount		$ 0	$ 0	$ 0
Discrete tax benefits realized upon adoption of ASU		1,600,000
Accumulated other comprehensive loss
Home office and equipment [Abstract]
Cumulative effect to reclassify certain tax effects from accumulated other comprehensive loss	(10,400,000)	(10,422,000)
Retained earnings (deficit)
Home office and equipment [Abstract]
Cumulative effect to reclassify certain tax effects from accumulated other comprehensive loss	$ 10,400,000	$ 10,422,000
Minimum
Home office and equipment [Abstract]
Estimated useful life		3 years
Award vesting period		1 year
Maximum
Home office and equipment [Abstract]
Estimated useful life		45 years
Award vesting period		3 years