Government Grants - Summary of Changes in Government Grants (Details) - KRW (₩) ₩ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Changes in government grants
Beginning balance	₩ 538,977	₩ 521,101
Receipt	59,503	57,207
Acquisitions	(6,806)	(5,544)
Offset the items of depreciation expense and others	(35,421)	(36,589)
Disposals	(1,936)	(2,842)
Revenue	4,789	239	₩ 301
Others	2,337	5,405
Ending balance	561,443	538,977	521,101
Cash
Changes in government grants
Beginning balance	0	0
Receipt	59,503	57,207
Acquisitions	0	0
Offset the items of depreciation expense and others	0	0
Disposals	0	0
Revenue	4,789	239
Others	(64,292)	(57,446)
Ending balance	0	0	0
Land
Changes in government grants
Beginning balance	27,404	27,405
Receipt	0	0
Acquisitions	0	0
Offset the items of depreciation expense and others	0	0
Disposals	(1)	(1)
Revenue	0	0
Others	0	0
Ending balance	27,403	27,404	27,405
Buildings
Changes in government grants
Beginning balance	46,227	50,437
Receipt	0	0
Acquisitions	0	0
Offset the items of depreciation expense and others	(4,508)	(5,070)
Disposals	0	0
Revenue	0	0
Others	(1)	860
Ending balance	41,718	46,227	50,437
Structures
Changes in government grants
Beginning balance	157,881	165,608
Receipt	0	0
Acquisitions	0	0
Offset the items of depreciation expense and others	(9,458)	(9,562)
Disposals	(1,330)	(1,611)
Revenue	0	0
Others	2,644	3,446
Ending balance	149,737	157,881	165,608
Machinery
Changes in government grants
Beginning balance	119,824	127,126
Receipt	0	0
Acquisitions	0	0
Offset the items of depreciation expense and others	(16,076)	(17,413)
Disposals	(522)	(1,230)
Revenue	0	0
Others	2,320	11,341
Ending balance	105,546	119,824	127,126
Vehicles
Changes in government grants
Beginning balance	2,837	2,045
Receipt	0	0
Acquisitions	0	0
Offset the items of depreciation expense and others	(1,233)	(960)
Disposals	(8)	0
Revenue	0	0
Others	1,149	1,752
Ending balance	2,745	2,837	2,045
Equipment
Changes in government grants
Beginning balance	5,932	6,608
Receipt	0	0
Acquisitions	0	0
Offset the items of depreciation expense and others	(2,118)	(2,011)
Disposals	0	0
Revenue	0	0
Others	101	1,335
Ending balance	3,915	5,932	6,608
Tools
Changes in government grants
Beginning balance	62	99
Receipt	0	0
Acquisitions	0	0
Offset the items of depreciation expense and others	(341)	(38)
Disposals	0	0
Revenue	0	0
Others	1,585	1
Ending balance	1,306	62	99
Construction in progress
Changes in government grants
Beginning balance	173,474	135,926
Receipt	0	0
Acquisitions	(6,806)	(5,544)
Offset the items of depreciation expense and others	0	0
Disposals	(75)	0
Revenue	0	0
Others	56,973	43,092
Ending balance	223,566	173,474	135,926
Investment properties
Changes in government grants
Beginning balance	22	21
Receipt	0	0
Acquisitions	0	0
Offset the items of depreciation expense and others	(1)	(1)
Disposals	0	0
Revenue	0	0
Others	1	2
Ending balance	22	22	21
Software
Changes in government grants
Beginning balance	413	174
Receipt	0	0
Acquisitions	0	0
Offset the items of depreciation expense and others	(229)	(85)
Disposals	0	0
Revenue	0	0
Others	660	324
Ending balance	844	413	174
Development expenditures
Changes in government grants
Beginning balance	2,121	3,477
Receipt	0	0
Acquisitions	0	0
Offset the items of depreciation expense and others	(1,364)	(1,356)
Disposals	0	0
Revenue	0	0
Others	182	0
Ending balance	939	2,121	3,477
Intangible assets under development
Changes in government grants
Beginning balance	2,458	2,108
Receipt	0	0
Acquisitions	0	0
Offset the items of depreciation expense and others	0	0
Disposals	0	0
Revenue	0	0
Others	1,015	350
Ending balance	3,473	2,458	2,108
Others
Changes in government grants
Beginning balance	322	67
Receipt	0	0
Acquisitions	0	0
Offset the items of depreciation expense and others	(93)	(93)
Disposals	0	0
Revenue	0	0
Others	0	348
Ending balance	₩ 229	₩ 322	₩ 67

The amount of assistance by government in the form of transfers of resources to an entity in return for past or future compliance with certain conditions relating to the operating activities of the entity, recognised as deferred income. They exclude those forms of government assistance that cannot reasonably have a value placed upon them and transactions with government that cannot be distinguished from the normal trading transactions of the entity. [Refer: Deferred income other than contract liabilities; Government [member]]

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