Common Stock Activity (Summary of Share Activity) (Details)	6 Months Ended				12 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Dec. 31, 2012	Dec. 31, 2011
Rollforward of Share Activity, Common and Treasury Shares
Common shares outstanding, beginning balance	76,448,000		80,569,000		80,569,000
Shares issued for stock option exercises	313,303		32,000
Shares issued for restricted stock awards	35,772		129,126
Other shares issued, net	130,000		5,000
Common stock repurchases			(2,906,000)	[1]	(4,900,000)	(4,600,000)
Common shares outstanding, ending balance	76,727,000		77,829,000		76,448,000	80,569,000
Treasury shares, beginning balance	9,467,286		4,594,000		4,594,000
Treasury shares, ending balance	9,467,286		7,500,000		9,467,286	4,594,000
Investor [Member] | Common Stock Outstanding [Member]
Rollforward of Share Activity, Common and Treasury Shares
Shares contributed by shareholder, former owner of acquired business	(200,000)	[2]

[1] (1) See Note 2 - Earnings Per Share for share repurchase plan details.

[2] (2) See Note 12 - Stock-Based Compensation and Other Employee Benefit Plans for contributed share details.