XML 201 R184.htm IDEA: XBRL DOCUMENT
v3.20.1

Deferred Income Tax and Income Tax Expense - Summary of Movement in Deferred Income Tax Assets and Liabilities (Detail) - KRW (₩) ₩ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | ₩ 260,584 | ₩ 583,760 |
Changes in accounting policy |  | (374,307) |
Statement of operations | (199,527) | 15,016 | ₩ (1,771)
Other comprehensive income | (61,669) | 36,115 |
Ending | (612) | 260,584 | 583,760
Deferred tax liabilities derivative assets [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Statement of operations | (10,250) |  |
Other comprehensive income | (648) |  |
Ending | (10,898) |  |
Deferred tax liabilities available for sale financial assets [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning |  | (30,520) |
Changes in accounting policy |  | 30,520 |
Ending |  |  | (30,520)
Deferred tax liabilities investment in subsidiaries associates and joint ventures [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | (93,604) | (96,650) |
Statement of operations | (14,622) | 2,867 |
Other comprehensive income | 35 | 179 |
Ending | (108,191) | (93,604) | (96,650)
Deferred tax liabilities depreciation [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | (424) |  |
Statement of operations | (11,182) | (424) |
Ending | (11,606) | (424) |
Deferred tax liabilities advanced depreciation provision [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | (313,184) | (248,592) |
Statement of operations | 63 | (64,592) |
Ending | (313,121) | (313,184) | (248,592)
Deferred tax liabilities deposits for severance benefits [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | (398,982) | (387,856) |
Statement of operations | (99,126) | (11,126) |
Other comprehensive income | 1,255 |  |
Ending | (496,853) | (398,982) | (387,856)
Deferred tax liabilities accrued income [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | (1,558) | (2,150) |
Statement of operations | 17 | 592 |
Ending | (1,541) | (1,558) | (2,150)
Deferred tax liabilities reserve for technology and human resource development [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | (204) | (314) |
Statement of operations |  | 110 |
Ending | (204) | (204) | (314)
Other deferred tax liabilities [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | (284,255) | (108,749) |
Statement of operations | (238,725) | (175,506) |
Other comprehensive income | (170) |  |
Ending | (523,150) | (284,255) | (108,749)
Deferred tax liabilities prepaid expenses [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | (369,916) |  |
Changes in accounting policy |  | (352,139) |
Statement of operations | (40,947) | (17,777) |
Ending | (410,863) | (369,916) |
Deferred tax derivative assets [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 8,341 | 24,724 |
Statement of operations | (850) | (26,128) |
Other comprehensive income | (7,491) | 9,745 |
Ending |  | 8,341 | 24,724
Deferred tax assets provision for impairment or trade receivables [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 99,887 | 121,656 |
Changes in accounting policy |  | (9,096) |
Statement of operations | (15,816) | (12,673) |
Ending | 84,071 | 99,887 | 121,656
Deferred tax assets inventory valuation [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 121 |  |
Statement of operations | (98) | 121 |
Ending | 23 | 121 |
Deferred tax assets contribution for construction [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 16,800 | 18,271 |
Statement of operations | (646) | (1,471) |
Ending | 16,154 | 16,800 | 18,271
Deferred tax assets accrued expenses [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 127,897 | 106,168 |
Statement of operations |  | 21,729 |
Ending |  | 127,897 | 106,168
Deferred Tax Assets Provisions [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 36,178 | 24,079 |
Statement of operations | (3,354) | 12,099 |
Ending | 32,824 | 36,178 | 24,079
Deferred tax assets property, plant and equipment [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 230,278 | 232,074 |
Statement of operations | (1,623) | (1,796) |
Ending | 228,655 | 230,278 | 232,074
Deferred Tax assets assets retirement obligation [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 24,532 | 20,836 |
Statement of operations | 4,484 | 3,696 |
Ending | 29,016 | 24,532 | 20,836
Deferred tax assets withholding of facilities expenses [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 6,609 | 7,382 |
Statement of operations | (426) | (773) |
Ending | 6,183 | 6,609 | 7,382
Deferred tax assets deduction of installment receivables [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 42 |  |
Statement of operations | 6 | 42 |
Ending | 48 | 42 |
Deferred tax assets gain or loss foreign currency translation [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 10,672 | 143 |
Statement of operations | 10,005 | 10,529 |
Ending | 20,677 | 10,672 | 143
Deferred tax assets deferred revenue [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 39,641 | 26,334 |
Changes in accounting policy |  | 15,809 |
Statement of operations | (3,841) | (2,502) |
Ending | 35,800 | 39,641 | 26,334
Deferred tax assets real-estate sales [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 21,728 | 8,698 |
Changes in accounting policy |  | 661 |
Statement of operations | (8,043) | 12,369 |
Ending | 13,685 | 21,728 | 8,698
Deferred tax assets tax loss carryforward [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 4,063 | 2,699 |
Statement of operations |  | 1,364 |
Ending |  | 4,063 | 2,699
Other deferred tax assets [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 531,549 | 247,702 |
Changes in accounting policy |  | 154 |
Statement of operations | 174,177 | 284,742 |
Other comprehensive income | (2,949) | (1,049) |
Ending | 708,437 | 531,549 | 247,702
Deferred tax assets [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 1,673,777 | 1,307,815 |
Changes in accounting policy |  | 10,418 |
Statement of operations | 235,361 | 304,035 |
Other comprehensive income | (3,658) | 51,509 |
Ending | 1,905,480 | 1,673,777 | 1,307,815
Deferred tax assets defined benefit liabilities [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 513,842 | 467,049 |
Statement of operations | 48,847 | 3,980 |
Other comprehensive income | 6,782 | 42,813 |
Ending | 569,471 | 513,842 | 467,049
Deferred tax assets tax credit carry forwards [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 102,898 | 150,776 |
Statement of operations | 25,347 | (47,878) |
Ending | 128,245 | 102,898 | 150,776
Deferred tax liabilities contract assets [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | (11,505) |  |
Changes in accounting policy |  | (23,663) |
Statement of operations | (42,245) | 12,158 |
Ending | (53,750) | (11,505) |
Deferred tax liabilities financial assets at fair value through profit or loss [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | (661) |  |
Changes in accounting policy |  | (30,856) |
Statement of operations | 338 | 30,195 |
Ending | (323) | (661) |
Deferred tax liabilities Financial assets at fair value through other comprehensive income [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | (41,798) |  |
Changes in accounting policy |  | (8,587) |
Statement of operations | (3,556) | (17,638) |
Other comprehensive income | (58,483) | (15,573) |
Ending | (103,837) | (41,798) |
Deferred tax assets unsettled expenses [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 127,897 |  |
Statement of operations | 32,539 |  |
Ending | 160,436 | 127,897 |
Deferred tax assets trade receivables [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 1,597 |  |
Changes in accounting policy |  | 2,890 |
Statement of operations |  | (1,293) |
Ending |  | 1,597 |
Temporary differences [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | 157,686 | 432,984 |
Changes in accounting policy |  | (374,307) |
Statement of operations | (224,874) | 62,894 |
Other comprehensive income | (61,669) | 36,115 |
Ending | (128,857) | 157,686 | 432,984
Deferred tax liabilities [member] |  |  |
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] |  |  |
Beginning | (1,516,091) | (874,831) |
Changes in accounting policy |  | (384,725) |
Statement of operations | (460,235) | (241,141) |
Other comprehensive income | (58,011) | (15,394) |
Ending | ₩ (2,034,337) | ₩ (1,516,091) | ₩ (874,831)

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