Amount of the cumulative effect on retained earnings before related income tax effect.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22663-107794

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Amount of the related income tax effect of a cumulative effect on retained earnings.

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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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Amount of the reclassification adjustment out of AOCI due to a new accounting pronouncement.

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Quota Share Reinsurance Percentage

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Significant Accounting Policies (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	May 30, 2014
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Cumulative Effect on Retained Earnings, before Tax	$ 233,800
Cumulative Effect on Retained Earnings, Tax	(11,900)
Grey Castle Life Reinsurance SAC Ltd
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Quota share reinsurance agreement, percentage			100.00%
Accounting Standards Update 2018-02
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Reclassification due to adoption of new accounting pronouncement	(3,903)
Accounting Standards Update 2018-02 \| AOCI Attributable to Parent [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Reclassification due to adoption of new accounting pronouncement	$ (3,903)	$ 0