CONSOLIDATED CONDENSED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Fixed maturities at fair value, amortized cost	$ 41,090,638	$ 39,832,724
Fixed maturities at amortized cost, fair value	2,796,603	2,733,340
Equity securities, cost	763,914	768,423
Mortgage loans, related to securitizations	245,202	277,964
Investment real estate, accumulated depreciation	113	252
Other intangibles, accumulated amortization	126,709	79,226
Property and equipment, accumulated depreciation	$ 20,185	$ 17,450
Common Stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common Stock, shares authorized (in shares)	5,000	5,000
Common Stock, shares issued (in shares)	1,000	1,000
Net unrealized gains (losses) on investments, income tax	$ (53,167)	$ (349,541)
Net unrealized (losses) gains relating to other-than-temporary impaired investments for which a portion has been recognized in earnings, income tax	(27)	(3,864)
Accumulated loss - derivatives, income tax	549	391
Postretirement benefits liability adjustment, income tax	$ 578	$ 578