Stock Plans and Share-Based Compensation - Shares Issued Under Employee Stock Purchase Plan (Details) - ESPP - Employee Stock Purchase Plan - $ / shares shares in Thousands	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)	396	366
Weighted average purchase price per share (in dollars per share)	$ 19.33	$ 20.50

Number of shares issued under share-based payment arrangement.

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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration