Earnings Per Share (Schedule Of Convertible Debt Information) (Detail) (Convertible Debt [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
New 4.0% Notes [Member]
Earnings Per Share [Line Items]
Principal amount	$ 105,322	[1]	$ 105,322	[1]
Conversion price per share	$ 15.76		$ 15.76		$ 15.76
Number of conversion shares, principal amount	6,683		6,683
Excess over principal amount	19,494		20,968
Weighted average equivalent premium shares (in thousands)	1,044		1,067		0
New 4.0% Notes [Member] | Weighted Average [Member]
Earnings Per Share [Line Items]
Weighted average actual per share price	$ 18.68		$ 18.90
New 4.25% Notes [Member]
Earnings Per Share [Line Items]
Principal amount	97,000	[1]	97,000	[1]
Conversion price per share	$ 15.48		$ 15.48		$ 15.48
Number of conversion shares, principal amount	6,268		6,268
Excess over principal amount	$ 20,064		$ 21,139
Weighted average equivalent premium shares (in thousands)	1,074		1,095		0
New 4.25% Notes [Member] | Weighted Average [Member]
Earnings Per Share [Line Items]
Weighted average actual per share price	$ 18.68		$ 18.88

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