Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 3: 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)
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Common Stock, Preferred Stock and Equity Plans - Share Repurchase Program (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Jul. 31, 2019	Jun. 30, 2019
Equity, Class of Treasury Stock [Line Items]
Repurchases of common stock	$ 192,015,000	$ 350,043,000
Share Repurchase Program 2018
Equity, Class of Treasury Stock [Line Items]
Number of shares authorized to be repurchased		$ 500,000,000.0		$ 500,000,000.0
Repurchases of common stock (shares)	832,186	2,093,891
Repurchases of common stock	$ 150,000,000.0	$ 350,000,000.0
Share Repurchase Program 2019
Equity, Class of Treasury Stock [Line Items]
Number of shares authorized to be repurchased			$ 500,000,000.0
Repurchases of common stock (shares)	213,548
Repurchases of common stock	$ 36,000,000.0
Number of shares remaining for repurchases	$ 464,000,000.0