Goodwill and Intangible Assets - Goodwill Rollforward (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Aug. 31, 2012
Goodwill [Roll Forward]
Carrying amount of goodwill, December 31, 2012	$ 274,884	$ 25,400
Currency translation adjustments	168
Fair value adjustments	387
Carrying amount of goodwill, December 31, 2013	275,439	25,400
Domestic Segment
Goodwill [Roll Forward]
Carrying amount of goodwill, December 31, 2012	248,498
Currency translation adjustments	0
Fair value adjustments	0
Carrying amount of goodwill, December 31, 2013	248,498
International Segment
Goodwill [Roll Forward]
Carrying amount of goodwill, December 31, 2012	26,386
Currency translation adjustments	168
Fair value adjustments	387
Carrying amount of goodwill, December 31, 2013	$ 26,941

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=14024403&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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- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the 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

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 16

-URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e961-128460

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- Details

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- Definition

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

+ Details

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