Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2012

Fair Value Measurements

Recurring Fair Value Measurements

	Fair Value as of December 31, 2012
	Level 1		Level 2		Level 3		Total
	(In thousands)
Assets:
Short-term investments:
Available-for-sale equity securities from energy industry	$	163,924	$	10,686	$	—	$	174,610
Available-for-sale debt securities:
Commercial paper and CDs	206		—		—		206
Corporate debt securities	—		23,399		—		23,399
Mortgage-backed debt securities	—		244		—		244
Mortgage-CMO debt securities	—		523		—		523
Asset-backed debt securities	1,595		—		—		1,595
Trading equity securities from energy industry	52,705		—		—		52,705
Total short-term investments	$	218,430	$	34,852	$	—	$	253,282

Fair Value of Financial Instruments

	As of December 31,
	2012				2011
	Carrying Value		Fair Value		Carrying Value		Fair Value
	(In thousands)
6.15% senior notes due February 2018	$	968,708	$	1,164,813	$	967,490	$	1,113,986
9.25% senior notes due January 2019	1,125,000		1,492,819		1,125,000		1,419,514
5.00% senior notes due September 2020	697,648		770,707		697,343		734,475
4.625% senior notes due September 2021	697,907		755,517		697,667		708,176
5.375% senior notes due August 2012	—		—		274,604		281,188
Subsidiary preferred stock	69,188		68,625		69,188		68,625
Revolving credit facilities	890,000		890,000		860,000		860,000
Other	437		437		1,712		1,712
	$	4,448,888	$	5,142,918	$	4,693,004	$	5,187,676