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Recent Accounting Developments	3 Months Ended
	Mar. 31, 2012
Recent Accounting Developments
Recent Accounting Developments	18.   Recent Accounting Developments         In May 2011, the Financial Accounting Standards Board issued an update to the fair value measurements and disclosures guidance. The new guidance clarifies existing fair value measurement principles and expands certain disclosure requirements, particularly for measurements categorized as Level 3. The amendment is effective for interim and fiscal periods beginning after December 15, 2011. The Company adopted this guidance in the first quarter of 2012. Adoption of this new guidance did not have a material impact on the Company's Consolidated Financial Statements.

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Disclosure of changes in accounting principles, including adoption of new accounting pronouncements, that describes the new methods, amount and effects on financial statement line items.

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