Shareholders' Equity (Schedule Of Common Stock Outstanding Roll Forward) (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Shares issued:
Total shares issued at beginning of period			36,369,868
Shares cancelled, shares			(940,445)
Total shares issued at end of period	35,429,423		35,429,423
Treasury shares:
Treasury shares issued, balance at beginning of period			1,572,087
Shares repurchased, shares	508,328	905,383	940,445	2,336,187
Shares issued out of treasury			(318,495)
Shares cancelled, shares			(940,445)
Total treasury shares at end of period	1,253,592		1,253,592
Total shares outstanding at end of period	34,175,831		34,175,831		34,797,781