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Benefit Plans (Fair Values Of Nonvested Performance Shares And Performance Units) (Details) | 12 Months Ended
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Dec. 31, 2019 $ / shares shares
Performance Shares Liability Awards [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Nonvested, December 31 (in shares/awards) | 131,872
Performance Units Liability Awards [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Nonvested, December 31 (in shares/awards) | 34,574
2018 Grant [Member] | Performance Shares Liability Awards [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Nonvested, December 31 (in shares/awards) | 68,307
Estimated payout percentage based on performance criteria | 118.00%
Fair values of each nonvested award (in dollars per share) | $ / shares | $ 64.57
2018 Grant [Member] | Performance Units Liability Awards [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Nonvested, December 31 (in shares/awards) | 17,622
Estimated payout percentage based on performance criteria | 118.00%
Fair values of each nonvested award (in dollars per share) | $ / shares | $ 64.57
2017 Grant [Member] | Performance Shares Liability Awards [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Nonvested, December 31 (in shares/awards) | 63,565
Estimated payout percentage based on performance criteria | 155.00%
Fair values of each nonvested award (in dollars per share) | $ / shares | $ 84.82
2017 Grant [Member] | Performance Units Liability Awards [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Nonvested, December 31 (in shares/awards) | 16,952
Estimated payout percentage based on performance criteria | 155.00%
Fair values of each nonvested award (in dollars per share) | $ / shares | $ 84.82

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- Definition Estimated Payout Percentage + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + References 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 (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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