Stock-Based Compensation - Incentive Units (Details) (Incentive Units [Member], Common Class A [Member])	12 Months Ended
Dec. 31, 2014
Incentive Units [Member] \| Common Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward]
Beginning balance (in shares)	49,000
Issued (in shares)	0
Vested (in shares)	0
Exercised (in shares)	(11,000)
Canceled (in shares)	0
Ending balance (in shares)	38,000

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

Number of non-option equity instruments exercised by participants.

+ References

+ Details

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- Definition

Number of shares under non-option equity instrument agreements that were either cancelled or expired.

+ References

+ Details

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- Definition

Net number of non-option equity instruments granted to participants.

+ References

+ Details

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Details

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