Equity And Other Investments (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010
Schedule Of Equity And Other Investments [Line Items]
Long-term equity and other investment	$ 11,945		$ 13,210
Short-term equity and other investment	1,703		1,703
Equity and other investments, total	$ 13,648	$ 9,608	$ 14,913	$ 17,256	$ 13,203	$ 18,385