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Earnings per Share - Composition of Weighted-Average Common Shares (Denominator) Used in Basic and Diluted Earnings Per Share (Detail) - $ / shares | 3 Months Ended
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Mar. 31, 2021 | Mar. 31, 2020
Earnings Per Share [Abstract] |  |
Weighted Average Number of Shares Issued, Basic | 113,914,902 | 113,914,902
Average treasury shares (in shares) | (17,718,410) | (15,672,850)
Weighted Average Number of Shares, Deferred Compensation Plans | (55,544) | (38,453)
Average unearned nonvested shares | (114,082) | (79,972)
Weighted average common shares and common stock equivalents used to calculate basic earnings per share (in shares) | 96,026,866 | 98,123,627
Additional common stock equivalents (nonvested stock) used to calculate diluted earnings per share | 151,200 | 196,441
Weighted Average Number Of Additional Shares Deferred Compensation Plan | 55,581 | 41,426
Weighted average common shares and common stock equivalents used to calculate diluted earnings per share (in shares) | 96,233,647 | 98,361,494
Basic Earnings per Share (in dollars per share) | $ 0.41 | $ 0.05
Diluted Earnings per Share (in dollars per share) | $ 0.41 | $ 0.05

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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22583-107794 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 11 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=121326447&loc=d3e1448-109256 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22595-107794 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 11 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=121326447&loc=d3e1337-109256 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 55 -Paragraph 52 -URI http://asc.fasb.org/extlink&oid=120380238&loc=d3e4984-109258 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(23)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 55 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=120380238&loc=d3e3842-109258 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22644-107794 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(25)) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121326447&loc=d3e1252-109256 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 60B -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121326447&loc=SL5780133-109256 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(27)) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 + Details
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 55 -Paragraph 52 -URI http://asc.fasb.org/extlink&oid=120380238&loc=d3e4984-109258 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22644-107794 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 55 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=120380238&loc=d3e3842-109258 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121326447&loc=d3e1252-109256 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 11 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22595-107794 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22583-107794 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 60B -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121326447&loc=SL5780133-109256 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(27)) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(23)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 11 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22694-107794 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=121326447&loc=d3e1337-109256 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(25)) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 + Details
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