Commitments And Contingencies (Estimated Cost To Replace All Such Annuities For Which The Company Was Contingently Liable) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
The Prudential [Member]
Loss Contingencies [Line Items]
Estimated cost to replace annuities	$ 146,923	$ 146,507
Unaffiliated Life Insurance Company [Member]
Loss Contingencies [Line Items]
Estimated cost to replace annuities	$ 33,107	$ 33,860