Share-Based Compensation Plans - Weighted Average Exercise Price, ESPP (Details) - Employee Stock Purchase Plan - $ / shares shares in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted and exercised (in shares)	228	199	160
Weighted average exercise plan (in usd per share)	$ 47.97	$ 54.89	$ 66.72

Per share weighted-average price paid for shares purchased on open market for issuance 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=116856206&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant