Stockholders' Equity - Activities Under Equity Plan (Details) - shares	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021
ESPP
Share-based Compensation Arrangement By Share-based Payment Award, Shares Authorized [Roll Forward]
Shares available for grant (in shares)	133,184
ESPP common stock purchased by eligible employees (in shares)	0	0
Shares available for grant (in shares)	133,184
Unvested RSUs, DSUs and Restricted Stock
Share-based Compensation Arrangement By Share-based Payment Award, Shares Authorized [Roll Forward]
RSU, DSU, and restricted stock awarded to eligible employees, net of forfeitures (in shares)	(454,429)
Unvested RSUs, DSUs and Restricted Stock \| 2012 Equity Plan
Share-based Compensation Arrangement By Share-based Payment Award, Shares Authorized [Roll Forward]
Shares available for grant (in shares)	990,129
RSU, DSU, and restricted stock awarded to eligible employees, net of forfeitures (in shares)	(319,418)
Shares available for grant (in shares)	670,711

Share-based Compensation Arrangement By Share-based Payment Award, Shares Authorized [Roll Forward]

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(01)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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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 https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Name Accounting Standards Codification
-Topic 210
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-Section S99
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-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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