Dividends (Dividends Paid In Total And Per Share) (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Feb. 01, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Dividends [Abstract]
Total paid		$ 138,478	$ 137,886	$ 137,201
Per share (in dollars per share)		$ 2.5025	$ 2.4925	$ 2.4825
Maximum dividend payable without prior permission of DOI of states domicile		$ 145,000
Payments of ordinary dividends		$ 135,000	$ 109,000	$ 111,000
Subsequent Event [Member]
Subsequent Event [Line Items]
Quarterly dividend declared (in dollars per share)	$ 0.6275