Goodwill, Intangible Assets and In-Process Revenue Contracts - Summary of Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 317,684	$ 317,964
Accumulated Amortization	(223,018)	(210,066)
Net Carrying Amount	94,666us-gaap_FiniteLivedIntangibleAssetsNet	107,898us-gaap_FiniteLivedIntangibleAssetsNet
Customer contracts [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	316,684	316,684
Accumulated Amortization	(223,018)	(209,786)
Net Carrying Amount	93,666	106,898
Other intangible assets [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,000	1,280
Accumulated Amortization		(280)
Net Carrying Amount	$ 1,000	$ 1,000

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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