Stockholders' Equity (Narrative) (Details) € in Millions	12 Months Ended
Dec. 31, 2020 USD ($) shares	Dec. 11, 2018 USD ($)	Apr. 25, 2017 USD ($)
Stockholders' Equity Note [Abstract]
Dividends	$ 59,200,000
Stock repurchase program, authorized amount \| $	$ 207,800,000	$ 300,000,000.0	$ 500,000,000.0
Canceled shares (in shares) \| shares	0

Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

Reference 1: 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)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

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Balance Type:	debit
Period Type:	duration