Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011
Income Taxes [Line Items]
Effective tax rate	23.30%	76.10%
Earnings of foreign entities	$ 9.7	$ 0.2
Unrecognized tax benefit	16.9		4.0
Accrued interest and penalties related to income tax liabilities	1.4		1.5
Decrease in unrecognized tax benefits due to the expiration of statutes of limitations and the settlement of various audits	1.6
S1 Corporation
Income Taxes [Line Items]
Increase in unrecognized tax benefits for uncertain tax positions	$ 13.3

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Unrecognized Tax Benefits, Increases Resulting From Acquisition

+ References

No definition available.

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- Definition

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 47

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

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- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Paragraph h

-Subparagraph 1(i)

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-Name Accounting Standards Codification

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-Section S99

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- Definition

The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 48

-Paragraph 21

-Subparagraph d

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- Definition

The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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-Name FASB Interpretation (FIN)

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-Glossary Unrecognized Tax Benefit

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- Definition

This element represents the total of accruals as of the date of the statement of financial position for interest recognized for an underpayment of income taxes computed by applying the applicable statutory rate of interest to the difference between a tax position recognized for financial reporting purposes and the amount previously taken or expected to be taken in a tax return of the entity and the amount of statutory penalties for a tax position claimed or expected to be claimed by the entity, in its tax return, that does not meet the minimum statutory threshold to avoid payment of penalties.

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