Fair Value Measurements

3 Months Ended

Mar. 31, 2013

Fair Value Measurements

Fair Value Measurements

6. Fair Value Measurements

        The fair values of the Company's cash and cash equivalents, joint interest and other receivables, restricted funds and investments approximate their carrying amounts due to their short-term duration. The hierarchy below lists three levels of fair value based on the extent to which inputs used in measuring fair value are observable in the market. The Company categorizes each of its fair value measurements as applicable to one of these three levels based on the lowest level input that is significant to the fair value measurement in its entirety. The levels are:

        Level 1—Quoted prices in active markets that are accessible at the measurement date for identical assets or liabilities. This category includes the Company's cash and money market funds.

        Level 2—Quoted prices in non-active markets or in active markets for similar assets or liabilities, and inputs other than quoted prices that are observable, for the asset or liability, either directly or indirectly, for substantially the full contractual term of the asset or liability being measured. This category includes the Company's U.S. Treasury bills, U.S. Treasury notes, U.S. Government agency securities, commercial paper, corporate bonds, municipal bonds and certificates of deposits.

        Level 3—Inputs that are generally unobservable and typically reflect management's estimate of assumptions that market participants would use in pricing the asset or liability. The Company does not currently have any financial instruments categorized as Level 3.

        The following tables summarize the Company's significant financial instruments as categorized by the fair value measurement hierarchy:

	Level 1				Level 2
									Balance as of March 31, 2013
	Carrying Value		Fair Value(1)		Carrying Value		Fair Value(1)
	($ in thousands)
Cash and cash equivalents:
Cash	$	27,409	$	27,409	$	—	$	—	$	27,409
Money market funds		205,791		205,791		—		—		205,791
Commercial paper		—		—		70,873		70,873		70,873
Corporate bonds		—		—		21,683		21,683		21,683
Subtotal		233,200		233,200		92,556		92,556		325,756
Short-term restricted funds:
U.S. Treasury bills		—		—		90,449		90,449		90,449
Subtotal		—		—		90,449		90,449		90,449
Short-term investments:
U.S. Treasury bills		—		—		26		26		26
Corporate bonds		—		—		682,639		682,639		682,639
Municipal bonds		—		—		—		—		—
Commercial paper		—		—		579,633		579,633		579,633
Certificates of deposits		—		—		25,000		25,000		25,000
Subtotal		—		—		1,287,298		1,287,298		1,287,298
Long-term restricted funds:
Money market funds		2,425		2,425		—		—		2,425
U.S. Treasury notes		—		—		302,783		302,783		302,783
Subtotal		2,425		2,425		302,783		302,783		305,208
Long-term investments:
Corporate bonds		—		—		512,754		512,754		512,754
Subtotal		—		—		512,754		512,754		512,754
Total	$	235,625	$	235,625	$	2,285,840	$	2,285,840	$	2,521,465

	Level 1				Level 2
									Balance as of December 31, 2012
	Carrying Value		Fair Value(1)		Carrying Value		Fair Value(1)
	($ in thousands)
Cash and cash equivalents:
Cash	$	65,935	$	65,935	$	—	$	—	$	65,935
Money market funds		1,105,148		1,105,148		—		—		1,105,148
Commercial paper		—		—		247,206		247,206		247,206
Corporate bonds		—		—		7,526		7,526		7,526
Subtotal		1,171,083		1,171,083		254,732		254,732		1,425,815
Short-term restricted funds:
U.S. Treasury bills		—		—		90,440		90,440		90,440
Subtotal		—		—		90,440		90,440		90,440
Short-term investments:
Corporate bonds		—		—		466,898		466,898		466,898
Commercial paper		—		—		315,769		315,769		315,769
Certificates of deposits		—		—		7,001		7,001		7,001
Subtotal		—		—		789,668		789,668		789,668
Long-term restricted funds:
Money market funds		2,318		2,318		—		—		2,318
U.S. Treasury bills		—		—		178,216		178,216		178,216
U.S. Treasury notes		—		—		215,118		215,118		215,118
Subtotal		2,318		2,318		393,334		393,334		395,652
Long-term investments:
Corporate bonds		—		—		36,267		36,267		36,267
Subtotal		—		—		36,267		36,267		36,267
Total	$	1,173,401	$	1,173,401	$	1,564,441	$	1,564,441	$	2,737,842

(1)

As of March 31, 2013 and December 31, 2012, the Company did not record any OTTI on these assets.