Stock-Based Compensation Plans - Employee Stock Purchase Plan (Details) - Employee Stock Purchase Plan shares in Millions	3 Months Ended
Mar. 31, 2020 $ / shares shares
Stock-Based Compensation Plans - Disclosures
Share purchases under employee stock purchase plan (in shares)	0.5
Weighted-average fair value of discount on employee stock purchase plan (in dollars per share) \| $ / shares	$ 4.70
Shares available to be issued under employee stock purchase plan (in shares)	0.9

Number of shares issued during the period as a result of an employee stock purchase plan.

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