Assets Pledged as Collateral or for Security - Summary of Assets Pledged as Collateral or for Security (Detail) $ in Thousands, $ in Thousands	Dec. 31, 2017 TWD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 TWD ($)
Assets Pledged As Collateral or For Security [Abstract]
Inventories related to real estate business	$ 4,822,043	$ 162,687	$ 16,813,023
Investment properties	8,119,436	273,935
Land use rights (recorded as long-term prepayment for lease)	6,813,751	229,884
Other financial assets (including current and non-current)	66,726	2,251	220,228
Total	$ 18,853,902	$ 636,097	$ 17,033,251

Assets pledged as collateral or for security.

No definition available.

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- Definition

Non Current Land Use Rights

+ References

No definition available.

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- Definition

The fair value of collateral held that is permitted to be sold or repledged in the absence of default by the owner of the collateral. [Refer: At fair value [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2017-01-01
-Paragraph 15
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_15_a&doctype=Standard
-URIDate 2017-03-09

+ Details

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- Definition

The amount of inventories pledged as security for liabilities. [Refer: Inventories]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 2
-IssueDate 2017-01-01
-Paragraph 36
-Subparagraph h
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=2&date=2017-03-01&anchor=para_36_h&doctype=Standard
-URIDate 2017-03-09

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- Definition

Expiry date 2019-01-01: The amount of property (land or a building - or part of a building - or both) held (by the owner or by the lessee under a finance lease) to earn rentals or for capital appreciation or both, rather than for: (a) use in the production or supply of goods or services or for administrative purposes; or (b) sale in the ordinary course of business. Effective 2019-01-01: The amount of property (land or a building - or part of a building - or both) held (by the owner or by the lessee as a right-of-use asset) to earn rentals or for capital appreciation or both, rather than for: (a) use in the production or supply of goods or services or for administrative purposes; or (b) sale in the ordinary course of business.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
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-IssueDate 2017-01-01
-Paragraph 76
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=40&date=2017-03-01&anchor=para_76&doctype=Standard
-URIDate 2017-03-09

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-URIDate 2017-03-09

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-URIDate 2017-03-09

+ Details

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- Definition

The amount of non-cash collateral assets (such as debt or equity instruments) provided to a transferee, for which the transferee has the right by contract or custom to sell or repledge the collateral.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2018-01-01
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-URIDate 2017-03-09

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2018-01-01
-Name IFRS
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-URIDate 2017-03-09

+ Details

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