Statutory Results Level 4 Regulatory Capital Requirements (Details)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Regulatory Capital Requirements [Abstract]
Statutory Accounting Practices, Risk Based Capital Requirements Compliance Assertion	The Company and all of its operating insurance subsidiaries had RBC ratios in excess of the minimum levels required by the applicable insurance regulations. The RBC ratios for the Company and its principal life insurance operating subsidiaries were all in excess of 300% of their Company Action Levels as of December 31, 2017 and 2016.	The Company and all of its operating insurance subsidiaries had RBC ratios in excess of the minimum levels required by the applicable insurance regulations. The RBC ratios for the Company and its principal life insurance operating subsidiaries were all in excess of 300% of their Company Action Levels as of December 31, 2017 and 2016.

Indicates whether the entity has met its capital adequacy needs as defined by the National Association of Insurance Commissioners as risk based capital requirements, and, if not met, a disclosure of the regulatory based capital level at which the entity is operating, and describes any uncertainties of the ultimate outcome of the entity's RBC position and management's plan with respect thereto, and currently imposed regulatory restrictions.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 505
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6486098&loc=d3e24790-158529

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