Cash Dividends (Narrative) (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	0 Months Ended		12 Months Ended
	Oct. 01, 2010	Apr. 01, 2010	Dec. 31, 2012	Dec. 31, 2011	Jan. 23, 2013	Jan. 18, 2012	Feb. 25, 2011	Jan. 31, 2010
Cash Dividends [Abstract]
Dividends Payable Quarterly, Amount Per Share (in Dollars per share)					$ 0.15	$ 0.15	$ 0.15	$ 0.50
Dividends Payable Dates To be Paid Day Month And Year					March 12, June 12, September 12, December 12 of 2013	March 14, June 14, September 14, December 14 of 2012	March 15, June 15, September 15, December 15 of 2011
Dividends Payable Dates of Record, Day, Month and Year					March 5, June 5, September 5, December 5 of 2013	March 7, June 7, September 7, December 7 of 2012	March 8, June 8, September 8, December 8 of 2011
Dividends, Cash (in Dollars)	$ 69,800	$ 59,900	$ 83,900	$ 83,800