Fair Value Measurements | 9 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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| Fair Value Measurements [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Fair Value Measurements | 14. Fair Value Measurements: As required, the Company's financial instruments are measured and reported at their estimated fair value. Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction. When available, the Company uses quoted prices in active markets to determine the fair values for its financial instruments (level one inputs), or absent quoted market prices, observable market-corroborated inputs over the term of the financial instruments (level two inputs). The Company does not have any unobservable inputs that are not corroborated by market inputs (level three inputs). The Company holds marketable securities associated with its non-qualified savings plan, which are valued based on readily available quoted market prices. The Company has utilized derivative instruments to manage its risk of changes in natural gas prices and interest rates. The fair value of the interest rate derivative instruments are determined using interest rate yield curves. The fair value of the natural gas derivative instruments are determined using market data of forward prices for all of the Company's contracts. The estimated fair values for each type of instrument are presented below (in millions).
Cash and cash equivalents, accounts receivable (net of allowance for bad debts) and payables are carried at cost, which approximates fair value due to their liquid and short-term nature. The Company's investments related to its nonqualified retirement plan of $6.1 million and $6.2 million as of September 30, 2011 and December 31, 2010, respectively, are stated at fair value based on quoted market prices. As of September 30, 2011, the estimated fair value of the fixed-rate 8% Senior Notes, based on available trading information, totaled $106.0 million compared with the aggregate principal amount at maturity of $100 million. The fair value at September 30, 2011 of amounts outstanding under the Credit Agreement, based upon available bid information received from the Company's lender, totaled approximately $370.8 million compared with the aggregate principal amount at maturity of $385.8 million. The fair values of the Company's natural gas contracts are based on rates for notional amounts maturing in each respective time-frame. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||