Lease - Summary of Details of Future Minimum Lease Payments under Finance Lease Contracts (Detail) - KRW (₩) ₩ in Millions	Dec. 31, 2017	Dec. 31, 2016
Disclosure of finance lease and operating lease by lessee [Line Items]
Total amount of minimum lease payments	₩ 220,635	₩ 211,457
Unrealized interest expense	43,758	30,743
Net amount of minimum lease payments	176,877	180,714
Less than 1 year [member]
Disclosure of finance lease and operating lease by lessee [Line Items]
Total amount of minimum lease payments	88,441	79,644
Net amount of minimum lease payments	68,651	64,008
1-5 years [Member]
Disclosure of finance lease and operating lease by lessee [Line Items]
Total amount of minimum lease payments	132,113	131,813
Net amount of minimum lease payments	108,146	₩ 116,706
More than 5 years [Member]
Disclosure of finance lease and operating lease by lessee [Line Items]
Total amount of minimum lease payments	81
Net amount of minimum lease payments	₩ 80

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

No definition available.

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- Definition

The amount representing the difference between the future minimum finance lease payments and their present value. Minimum lease payments are payments over the lease term that the lessee is or can be required to make, excluding contingent rent, costs for services and taxes to be paid by, and reimbursed to, the lessor, together with: (a) for a lessee, any amounts guaranteed by the lessee or by a party related to the lessee; or (b) for a lessor, any residual value guaranteed to the lessor by: (i) the lessee; (ii) a party related to the lessee; or (iii) a third party unrelated to the lessor that is financially capable of discharging the obligations under the guarantee.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2019-01-01
-Name IAS
-Number 17
-IssueDate 2017-01-01
-Paragraph 31
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=17&date=2017-03-02&anchor=para_31_b&doctype=Standard&book=B
-URIDate 2017-03-09

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- Definition

The amount of payments over the finance lease term that the lessee is or can be required to make, excluding contingent rent, costs for services and taxes to be paid by, and reimbursed to, the lessor, together with any amounts guaranteed by the lessee or by a party related to the lessee.

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- Definition

The present value of minimum finance lease payments payable. [Refer: Minimum finance lease payments payable]

+ References

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