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Repurchases Of Common Stock (Tables) | 3 Months Ended
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Mar. 31, 2018
Repurchases Of Common Stock [Abstract] |
Schedule Of Common Stock Repurchases |
﻿ |  |  |  |  |  |
﻿ |  | For the Three Months Ended
﻿ |  | March 31,
﻿ |  | 2018 |  | 2017
﻿ |  |  |  |  |  |
﻿Shares repurchased in the open market |  |  | 465 |  |  | 390
﻿Shares acquired through employee surrender for statutory tax withholding |  |  | 48 |  |  | 52
﻿Total shares repurchased |  |  | 513 |  |  | 442
﻿ |  |  |  |  |  |
﻿Cost of shares repurchased in the open market |  | $ | 86,188 |  | $ | 50,744
﻿Cost of shares for employee surrenders |  |  | 8,555 |  |  | 7,303
﻿Total cost of shares |  | $ | 94,743 |  | $ | 58,047
﻿ |  |  |  |  |  |
﻿Average cost per share - open market repurchase |  | $ | 185.23 |  | $ | 130.12
﻿Average cost per share - employee surrenders |  | $ | 178.83 |  | $ | 141.09
﻿Average cost per share - total |  | $ | 184.63 |  | $ | 131.41
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- Definition Tabular disclosure of treasury stock, including, but not limited to, average cost per share, description of share repurchase program, shares repurchased, shares held for each class of treasury stock. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23315-112656 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23285-112656 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23309-112656 + Details
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