Significant Accounting Policies - Stock-Based Compensation (Details)	12 Months Ended
Dec. 31, 2019
Performance Share Units
Stock-Based Compensation
Vesting period	3 years
Minimum \| Restricted Stock Units
Stock-Based Compensation
Vesting period	1 year
Maximum \| Restricted Stock Units
Stock-Based Compensation
Vesting period	5 years

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration