The component of interest expense comprised of the following: 1) Coupon Interest - interest expense charge for contractual coupon interest due on face value of the Senior Convertible Note 2) Accretion of Debt Discount - amortization of Original Issue Discount (which is charged to interest expense) on the Senior Convertible Note over the life of the Note, and 3) Amortization of Deferred Financing Costs - periodic charge against earnings over the life of the financing arrangement to which such costs relate.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders. Convertible notes can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

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The increase in the net discounted value of the proved oil and gas reserves due only to the passage of time.

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The component of interest expense comprised of the periodic charge against earnings over the life of the financing arrangement to which such costs relate. Alternate captions include Noncash Interest Expense.

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Aggregate amount of each class of warrants or rights outstanding.

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The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The price per share of the conversion feature embedded in the debt instrument.

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The ratio applied to the debt for purposes of determining the number of shares of the equity security into which the debt will be converted.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Interest rate stated in the contractual debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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The strike price on the price risk option contract such as a put option or a call option.

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Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings.

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-Number 210
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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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- Definition

The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

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The net cash inflow or outflow from other financing activities. This element is used when there is not a more specific and appropriate element in the taxonomy.

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Long-Term Debt (Details) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2011	Jun. 30, 2010	Mar. 31, 2011	Mar. 30, 2011	Mar. 29, 2011
Debt Instrument [Line Items]
Interest Expense, Debt	$ 1,438,000	$ 1,438,000
Accretion of Discount	1,834,000	1,834,000
Amortization of Financing Costs	326,000	326,000	0
Proceeds from Issuance of Warrants		31,740,000	0
Debt Instrument, Unamortized Discount	41,204,000	41,204,000
Class of Warrant or Right, Outstanding					0.5	3.5
Derivative, Price Risk Option Strike Price				$ 66.3528
Debt Instrument, Interest Rate, Effective Percentage	7.00%	7.00%
Payments of Debt Issuance Costs		8,015,000	0
Senior Convertible Note, Note Hedge, and Warrant Transaction Interest Expense	3,598,000	3,598,000
Senior convertible notes net of unamortized discount	188,796,000	188,796,000
Other Long-term Liabilities [Member] \| Convertible Debt [Member]
Debt Instrument [Line Items]
Senior Notes	187,000,000	187,000,000
Payments of Debt Issuance Costs	6,500,000
Equity [Member] \| Convertible Debt [Member]
Debt Instrument [Line Items]
Senior Notes	43,000,000	43,000,000
Senior Convertible Notes [Equity net of tax]	28,000,000	28,000,000
Payments of Debt Issuance Costs	1,500,000
Convertible Note Overallotment [Member]
Debt Instrument [Line Items]
Senior Notes	30,000,000	30,000,000
Convertible Debt [Member]
Debt Instrument [Line Items]
Senior Notes	230,000,000	230,000,000
Payments of Debt Issuance Costs	8,000,000
Convertible Debt [Member] \| Convertible Notes 2016 [Member]
Debt Instrument [Line Items]
Debt Conversion, Converted Instrument, Amount	0
Debt Instrument, Convertible, Conversion Price	$ 57.65	$ 57.65
Debt Instrument, Interest Rate, Stated Percentage	2.50%	2.50%
Debt Instrument, Convertible, Conversion Ratio		17.3458
Convertible Debt 1 [Member]
Debt Instrument [Line Items]
Senior Notes	200,000,000	200,000,000
Note Warrant2 [Member]
Debt Instrument [Line Items]
Proceeds from Issuance of Warrants	27,600,000
Convertible Note Hedge 2 [Member]
Debt Instrument [Line Items]
Proceeds from (Payments for) Other Financing Activities	5,600,000
Convertible Note Hedge [Member]
Debt Instrument [Line Items]
Proceeds from (Payments for) Other Financing Activities	42,700,000
Note Warrant [Member]
Debt Instrument [Line Items]
Proceeds from Issuance of Warrants	4,100,000
Convertible Note Hedge 1 [Member]
Debt Instrument [Line Items]
Proceeds from (Payments for) Other Financing Activities	37,100,000
Convertible Note/ Hedge Warrant, net [Member]
Debt Instrument [Line Items]
Proceeds from (Payments for) Other Financing Activities		$ 10,900,000