Goodwill (Changes in Goodwill) (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Goodwill [Roll Forward]
Balance, beginning of year, Goodwill, gross	$ 328,129us-gaap_GoodwillGross	$ 316,962us-gaap_GoodwillGross
Balance, beginning of year, Accumulated impairment lossses	(310,653)	(310,653)
Balance, beginning of year, Goodwill, Net	17,476us-gaap_Goodwill	6,309us-gaap_Goodwill
Increases due to current year acquisitions	460us-gaap_GoodwillAcquiredDuringPeriod	11,463us-gaap_GoodwillAcquiredDuringPeriod
Effects of foreign currency translation	(581)us-gaap_GoodwillTranslationAdjustments	(296)us-gaap_GoodwillTranslationAdjustments
Total goodwill increase (decrease)	(121)us-gaap_GoodwillPeriodIncreaseDecrease	11,167us-gaap_GoodwillPeriodIncreaseDecrease
Balance, end of year, Goodwill, gross	328,008us-gaap_GoodwillGross	328,129us-gaap_GoodwillGross
Balance, end of year, Accumulated impairment lossses	(310,653)	(310,653)
Balance, end of year, Goodwill, Net	$ 17,355us-gaap_Goodwill	$ 17,476us-gaap_Goodwill

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

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-Section 50

-Paragraph 1

-Subparagraph (a,h)

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Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

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