Dividends From Subsidiaries And Statutory Financial Information (Schedule of Combined Net Income and Policyholders' Surplus in Accordance with Statutory Accounting Practices) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Insurance [Abstract]
Amount available for dividend distribution without prior approval from regulatory authorities	$ 580,000
Net income	702,830	$ 813,303	$ 757,010
Policyholders' surplus	5,493,044	$ 5,296,435	$ 5,438,063
Increase in BIC's statutory capital and surplus	$ 231,000
Total Adjusted Capital percentage threshold	200.00%
BIC's Total Adjusted Capital balance	$ 5,300,000
BIC's Total Adjusted Capital balance as percentage of RBC Authorized Control Level	422.00%