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Shared-Based Payments (Summary of ESPP and ASPP Shares Issued) (Details) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule of Share-Based Compensation ESPP and ASPP Shares Granted [Line Items]
Stock Issued During Period Shares	613,678	540,337	635,521
Employee Stock [Member]
Schedule of Share-Based Compensation ESPP and ASPP Shares Granted [Line Items]
Stock Issued During Period Shares	72,952	70,448	75,093
Agent Stock Purchase Plan [Member]
Schedule of Share-Based Compensation ESPP and ASPP Shares Granted [Line Items]
Stock Issued During Period Shares	47,888	41,134	49,794

X

- Definition

[Line Items] for Tabular disclosure of schedule of Share-Based Compensation ESPP and ASPP Shares Granted

+ References

No definition available.

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- Definition

Number, after forfeiture, of shares or units issued under share-based payment arrangement. Excludes shares or units issued under employee stock ownership plan (ESOP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 2: 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=27012166&loc=d3e187085-122770

Reference 3: 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 4: 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(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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