Earnings Per Share (Schedule Of Convertible Debt Information) (Detail) (Convertible Debt [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011
New 4.0% Notes [Member]
Earnings Per Share [Line Items]
Principal amount	$ 105,322	[1]	$ 105,300	[1]	$ 105,322	[1]	$ 105,300	[1]
Conversion price per share	$ 15.76		$ 15.76		$ 15.76		$ 15.76
Number of conversion shares, principal amount	6,683				6,683
Excess over principal amount	14,208				10,975
Weighted average equivalent premium shares (in thousands)	794		1,366		631		1,166
New 4.0% Notes [Member] | Weighted Average [Member]
Earnings Per Share [Line Items]
Weighted average actual per share price	$ 17.89				$ 17.40
New 4.25% Notes [Member]
Earnings Per Share [Line Items]
Principal amount	97,000	[1]	97,000	[1]	97,000	[1]	97,000	[1]
Conversion price per share	$ 15.48		$ 15.48		$ 15.48		$ 15.48
Number of conversion shares, principal amount	6,268				6,268
Excess over principal amount	$ 15,106				$ 12,073
Weighted average equivalent premium shares (in thousands)	845		1,371		694		1,187
New 4.25% Notes [Member] | Weighted Average [Member]
Earnings Per Share [Line Items]
Weighted average actual per share price	$ 17.89				$ 17.40

[1] Dilutive shares associated with the New Notes are attributable to the premium over the respective conversion prices.