XML 43 R31.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Stockholders' Equity and Earnings Per Common Share (Tables) | 3 Months Ended
--- | ---
Mar. 31, 2018
Stockholders' Equity and Earnings Per Common Share [Abstract] |
Schedule of Basic and Diluted Earnings Per Share | Earnings Per Common Share Net income per common share is determined as follows:
| Three Months Ended March 31
| 2018 |  | 2017
| (in millions of dollars, except share data)
Numerator |  |  |
Net Income | $ | 273.5 |  |  | $ | 229.9 |
Denominator (000s) |  |  |
Weighted Average Common Shares - Basic | 221,894.0 |  |  | 229,429.6 |
Dilution for Assumed Exercises of Stock Options and Nonvested Stock Awards | 683.0 |  |  | 949.2 |
Weighted Average Common Shares - Assuming Dilution | 222,577.0 |  |  | 230,378.8 |
Net Income Per Common Share |  |  |
Basic | $ | 1.23 |  |  | $ | 1.00 |
Assuming Dilution | $ | 1.23 |  |  | $ | 1.00 |
Treasury Stock Transactions | Common Stock During the second quarter of 2017, our board of directors authorized the repurchase of up to $750.0 million of Unum Group's outstanding common stock through November 25, 2018. This authorization replaced the previous authorization of $750.0 million that was scheduled to expire on November 26, 2017. The remaining repurchase amount under the new program was $412.8 million at March 31, 2018. Common stock repurchases, which are accounted for using the cost method and classified as treasury stock until otherwise retired, were as follows:
| Three Months Ended March 31
| 2018 |  | 2017
| (in millions)
Shares Repurchased | 1.9 |  |  | 2.1 |
Cost of Shares Repurchased 1 | $ | 100.2 |  |  | $ | 100.0 |
1 Includes commissions of $0.2 million for the three months ended March 31, 2018, and a de minimis amount for the three months ended March 31, 2017.

X
- Definition Stockholders' Equity and Earnings Per Common Share [Abstract] + References No definition available. + Details
Name: | unm_StockholdersEquityandEarningsPerCommonShareAbstract
Namespace Prefix: | unm_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of an entity's basic and diluted earnings per share calculations, including a reconciliation of numerators and denominators of the basic and diluted per-share computations for income from continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
Name: | us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- 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
Name: | us-gaap_ScheduleOfTreasuryStockByClassTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration