XML 41 R28.htm IDEA: XBRL DOCUMENT
v3.6.0.2

Note 12 - Quarterly Financial Information (Unaudited) (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2016
Notes Tables |
Quarterly Financial Information [Table Text Block] |
|  | Quarter |
|  | First |  |  | Second |  |  | Third |  |  | Fourth |
2016: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating revenues |  | $ | 1,528,712 |  |  | $ | 1,615,026 |  |  | $ | 1,690,659 |  |  | $ | 1,721,062 |
Operating income |  | $ | 167,890 |  |  | $ | 175,792 |  |  | $ | 182,977 |  |  | $ | 194,361 |
Net earnings |  | $ | 100,098 |  |  | $ | 105,011 |  |  | $ | 109,425 |  |  | $ | 117,556 |
Basic earnings per share |  | $ | 0.89 |  |  | $ | 0.93 |  |  | $ | 0.97 |  |  | $ | 1.05 |
Diluted earnings per share |  | $ | 0.88 |  |  | $ | 0.92 |  |  | $ | 0.97 |  |  | $ | 1.05 |
2015: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating revenues |  | $ | 1,440,180 |  |  | $ | 1,539,957 |  |  | $ | 1,586,494 |  |  | $ | 1,621,015 |
Operating income |  | $ | 155,220 |  |  | $ | 173,735 |  |  | $ | 193,846 |  |  | $ | 192,893 |
Net earnings |  | $ | 91,932 |  |  | $ | 103,419 |  |  | $ | 115,139 |  |  | $ | 116,746 |
Basic earnings per share |  | $ | 0.79 |  |  | $ | 0.89 |  |  | $ | 1.00 |  |  | $ | 1.02 |
Diluted earnings per share |  | $ | 0.78 |  |  | $ | 0.88 |  |  | $ | 0.99 |  |  | $ | 1.01 |

X
- Definition Tabular disclosure of quarterly financial data. Includes, but is not limited to, financial information for fiscal quarters, cumulative effect of a change in accounting principle and earnings per share data. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a)-(j) -URI http://asc.fasb.org/extlink&oid=68076893&loc=d3e1280-108306 + Details
Name: | us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_TableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration