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Employee Plans - Summary of Information Regarding the Common Shares Issued Under the ESPP (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Employee Service Share Based Compensation Aggregate Disclosures [Abstract] |  |  |
Shares issued | 48,131 | 75,414 | 68,286
Issuance price ranges, Minimum | $ 59.56 | $ 47.80 | $ 52.79
Issuance price ranges, Maximum | $ 72.91 | $ 57.09 | $ 58.06
Issuance proceeds | $ 3,116 | $ 3,879 | $ 3,744

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- Definition Represents the maximum price that employees purchase common stock for under the employee purchase plan during the year. + References No definition available. + Details
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- Definition Represents the minimum price that employees purchase common stock for under the employee purchase plan during the year. + References No definition available. + Details
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- References No definition available. + Details
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- Definition Amount of cash inflow from issuance of shares under share-based payment arrangement. Excludes option exercised. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=116856206&loc=SL79508275-113901 + Details
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- Definition Number of shares issued under share-based payment arrangement. + 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=116856206&loc=d3e5070-113901 + Details
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