Estimated Future Amortization Expense on Payments for Processing Rights and Conversion Costs (Detail) (Contract Acquisition Costs, USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Payments for processing rights
Finite-Lived Intangible Assets [Line Items]
2013	$ 17,769
2014	16,699
2015	15,715
2016	13,059
2017	9,316
Conversion costs
Finite-Lived Intangible Assets [Line Items]
2013	14,622
2014	13,460
2015	11,552
2016	9,181
2017	$ 7,240

Amount of amortization expense expected to be recognized during the next fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=7658586&loc=d3e16323-109275

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Amount of amortization expense expected to be recognized during the fifth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense expected to be recognized during the fourth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense expected to be recognized during the third fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense expected to be recognized during the second fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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