Stock Incentive Plans - Securities To Be Issued and Remaining Available For Future Issuance (Details)	Dec. 31, 2020 $ / shares shares
2007 LTIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities to be issued upon vesting of RSUs and performance share awards (in shares)	1,624
Weighted-average exercise price of vesting of RSUs and performance share awards (in dollars per share) \| $ / shares	$ 0.01
Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in column 1) (in shares)	0
2010 LTIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities to be issued upon vesting of RSUs and performance share awards (in shares)	330,750
Weighted-average exercise price of vesting of RSUs and performance share awards (in dollars per share) \| $ / shares	$ 0.01
Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in column 1) (in shares)	0
2019 LTIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of securities to be issued upon vesting of RSUs and performance share awards (in shares)	430,643
Weighted-average exercise price of vesting of RSUs and performance share awards (in dollars per share) \| $ / shares	$ 0.01
Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in column 1) (in shares)	3,156,745

Share-based Compensation Arrangement by Share-based Payment Award, Number of Securities To Be Issued Upon Exercise of Outstanding Options, Warrants and Rights

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120381028&loc=d3e5070-113901

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