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v3.19.1

Revision of Prior Financial Statements - Summary of Consolidated Statement of Operations & Comprehensive Income (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Disclosure of changes in accounting policies, accounting estimates and errors [line items] |  |  |
Operating revenue | ₩ 23,436,050 | ₩ 23,546,929 | ₩ 23,164,202
Operating profit | 1,100,860 | 1,069,092 | 1,383,104
Profit before income tax | 1,033,977 | 816,997 | 1,166,755
Income tax expense | 314,565 | 270,656 | 334,910
Profit for the year | 719,412 | 546,341 | 831,845
Profit for the year attributable to the equity holders of the Controlling Company | 645,571 | 461,559 | 745,090
Total comprehensive income for the year | 664,784 | 478,053 | 826,175
Total comprehensive income for the year attributable to the equity holders of the Controlling Company | 589,179 | ₩ 413,149 | 738,413
As previously reported [member] |  |  |
Disclosure of changes in accounting policies, accounting estimates and errors [line items] |  |  |
Operating revenue | 23,704,320 |  | 23,120,878
Operating profit | 1,052,635 |  | 1,339,780
Profit before income tax | 965,030 |  | 1,123,431
Income tax expense | 296,621 |  | 328,314
Profit for the year | ₩ 668,409 |  | 795,117
Profit for the year attributable to the equity holders of the Controlling Company |  |  | 708,362
Total comprehensive income for the year |  |  | 789,447
Total comprehensive income for the year attributable to the equity holders of the Controlling Company |  |  | 701,685
Adjustments [member] |  |  |
Disclosure of changes in accounting policies, accounting estimates and errors [line items] |  |  |
Operating revenue |  |  | 43,324
Operating profit |  |  | 43,324
Profit before income tax |  |  | 43,324
Income tax expense |  |  | 6,596
Profit for the year |  |  | 36,728
Profit for the year attributable to the equity holders of the Controlling Company |  |  | 36,728
Total comprehensive income for the year |  |  | 36,728
Total comprehensive income for the year attributable to the equity holders of the Controlling Company |  |  | ₩ 36,728

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