Number Of Business Classes

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Tax Cuts And Jobs Act, Reclassification From AOCI To Retained Earnings, Tax Effect

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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- Definition

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
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-Section S99
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-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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The number of states the entity operates in as of the balance sheet date.

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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.

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Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands		3 Months Ended			6 Months Ended
	Jan. 01, 2018 USD ($)	Jun. 30, 2018 USD ($) state	Mar. 31, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) class_business state	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Jun. 30, 2016 USD ($)
Schedule of Available-for-sale Securities [Line Items]
Number of business classes \| class_business					2
Number of states in which entity operates \| state		50			50
Ownership percentage		50.00%			50.00%
Cumulative effect of adoption of ASU No. 2016-01, net of taxes							$ 0
Cumulative effect of adoption of ASU No. 2018-02, net of taxes					$ 0
Accumulated deficit
Schedule of Available-for-sale Securities [Line Items]
Cumulative effect of adoption of ASU No. 2016-01, net of taxes							556
Cumulative effect of adoption of ASU No. 2018-02, net of taxes					77
Accumulated Other Comprehensive Income (Loss)
Schedule of Available-for-sale Securities [Line Items]
Cumulative effect of adoption of ASU No. 2016-01, net of taxes							(556)
Cumulative effect of adoption of ASU No. 2018-02, net of taxes		$ 0	$ 77	$ 0	$ 77	$ 0
Accounting Standards Update 2016-01
Schedule of Available-for-sale Securities [Line Items]
Deferred income taxes	$ 500
Accounting Standards Update 2016-01 \| Accumulated deficit
Schedule of Available-for-sale Securities [Line Items]
Cumulative effect of adoption of ASU No. 2016-01, net of taxes	1,100
Accounting Standards Update 2016-01 \| Accumulated Other Comprehensive Income (Loss)
Schedule of Available-for-sale Securities [Line Items]
Cumulative effect of adoption of ASU No. 2016-01, net of taxes	$ (1,100)			$ 0		$ 0	$ (556)	$ 0	$ 0