Future Purchase Commitments (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012
Long-term Purchase Commitment [Line Items]
Remainder of 2012	$ 49,505
2013	24,530
2014	8,845
2015	674
2016	463
2017	203
Thereafter
Unconditional purchase obligations over next six years	$ 84,220

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Amount of the recorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 440

-SubTopic 10

-Section 50

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6394976&loc=d3e25383-109308

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 10

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 6

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Amount of the recorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year.

+ References

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Amount of the recorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year.

+ References

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Amount of the recorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year.

+ References

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Amount of the recorded unconditional purchase obligation maturing in the remainder of the fiscal year following the latest fiscal year ended.

+ References

No definition available.

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Amount of the recorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year.

+ References

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Amount of the recorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year.

+ References

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Amount of the recorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year.

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