Stockholders' Equity / (Deficit) - Shares Authorized and Outstanding (Details) - shares shares in Thousands	Sep. 30, 2018	Dec. 31, 2017
Stockholders' Equity / (Deficit)
Authorized shares of preferred stock	5,000
Authorized shares of common stock	100,000
Outstanding shares of common stock , net of repurchased stock	31,400	33,900
Preferred shares issued	0	0
Preferred shares outstanding	0	0

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
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- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

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-Publisher FASB
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- Definition

Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- References

No definition available.

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