Software and Other Intangible Assets - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Software, net	$ 206,757,000us-gaap_CapitalizedComputerSoftwareNet	$ 209,507,000us-gaap_CapitalizedComputerSoftwareNet
Software, accumulated amortization	132,400,000	121,600,000
Other intangible assets amortization expense	5,800,000us-gaap_AmortizationOfIntangibleAssets	6,500,000us-gaap_AmortizationOfIntangibleAssets
Software Marketed for External Sale [Member]
Finite-Lived Intangible Assets [Line Items]
Software, net	80,600,000	85,900,000
Software, amortization expense	3,900,000	3,500,000
Software Marketed for External Sale [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	3 years
Software Marketed for External Sale [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	10 years
Software Acquired or Developed for Internal Use [Member]
Finite-Lived Intangible Assets [Line Items]
Software, net	126,200,000	123,600,000
Software, amortization expense	$ 8,500,000	$ 5,200,000
Software Acquired or Developed for Internal Use [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	3 years
Software Acquired or Developed for Internal Use [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life	10 years

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

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- Definition

For each balance sheet presented, the amount of accumulated amortization for capitalized computer software costs.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 985

-SubTopic 20

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- Definition

For each income statement presented, the amount charged to expense for amortization of capitalized computer software costs.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 985

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- Definition

The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 985

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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