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Stock-Based Compensation Plans (Vested Restricted Stocks) (Details) - $ / shares | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Market Price at Vesting Date (in shares) | $ 25 | $ 22 | $ 20
Restricted Stock |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Shares granted (in shares) | 1,133,031 | 1,042,169 | 856,645
Restricted Stock | 1 Year |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Shares granted (in shares) | 39,627 | 0 | 0
Market Price at Vesting Date (in shares) | $ 22.19 |  |
Restricted Stock | 3 Years |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Shares granted (in shares) | 64,718 | 0 | 0
Market Price at Vesting Date (in shares) | $ 20.40 |  |
Restricted Stock | 3 Years | Minimum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Market Price at Vesting Date (in shares) | 20.40 | $ 20.21 | $ 18.97
Restricted Stock | 3 Years | Maximum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Market Price at Vesting Date (in shares) | $ 28.98 | $ 23.14 | $ 21.33
Restricted Stock | 4 Years |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Shares granted (in shares) | 773,698 | 762,749 | 628,015
Restricted Stock | 4 Years | Minimum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Market Price at Vesting Date (in shares) | $ 20.68 | $ 20.21 | $ 18.97
Restricted Stock | 4 Years | Maximum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Market Price at Vesting Date (in shares) | $ 28.98 | $ 23.14 | $ 21.33
Restricted Stock | 5 Years |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Shares granted (in shares) | 254,988 | 279,420 | 228,630
Restricted Stock | 5 Years | Minimum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Market Price at Vesting Date (in shares) | $ 20.68 | $ 20.21 | $ 18.97
Restricted Stock | 5 Years | Maximum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Market Price at Vesting Date (in shares) | $ 28.98 | $ 23.14 | $ 21.33

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- Definition Net number of non-option equity instruments granted to participants. + 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)(1)(iv)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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