Aggregate fair value of the redemption option.

No definition available.

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Balance Type:	credit
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- Definition

Bonds maturity year

+ References

No definition available.

+ Details

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- Definition

Conversion period of bonds.

+ References

No definition available.

+ Details

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- Definition

Conversion price

+ References

No definition available.

+ Details

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Data Type:	dtr-types:perShareItemType
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Period Type:	duration

- Definition

Effective interest rate on Contract.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Number of consecutive trading days for determining conversion price.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
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Period Type:	duration

- Definition

Percentage of current conversion price on Stock Exchange

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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Period Type:	instant

- Definition

Percentage of par value on USISH bonds.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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Period Type:	instant

- Definition

Secured domestic bonds conversion price.

+ References

No definition available.

+ Details

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Namespace Prefix:	asx_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of outstanding funds that the entity is obligated to repay.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 55
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_55&doctype=Standard
-URIDate 2021-03-24

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Balance Type:	credit
Period Type:	instant

- Definition

The interest rate on borrowings. [Refer: Borrowings]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 7
-IssueDate 2021-01-01
-Paragraph 7
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2021-en-r&anchor=para_7&doctype=Standard
-URIDate 2021-03-24

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The maturity of borrowings. [Refer: Borrowings]

+ References

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
-Paragraph 112
-Subparagraph c
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2021-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2021-03-24

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Details

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- Details

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Balance Type:
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- Details

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Balance Type:
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- Details

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- Details

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Bonds Payable - Additional Information (Detail) ¥ / shares in Units, $ / shares in Units, ¥ in Thousands, $ in Thousands, $ in Thousands	1 Months Ended			12 Months Ended
	Mar. 31, 2021 CNY (¥) ¥ / shares	Sep. 30, 2020 $ / shares	Dec. 31, 2017 TWD ($) $ / shares	Dec. 31, 2021 TWD ($) ¥ / shares	Dec. 31, 2021 USD ($)	Dec. 31, 2021 CNY (¥)
Unsecured Domestic Convertible Bonds [Member]
Disclosure of detailed information about borrowings [line items]
Bonds maturity period			3 years
Secured domestic bonds conversion price \| $ / shares		$ 4.8
Percentage of current conversion price on Stock Exchange		30.00%
Number of consecutive trading days for determining Conversion price		30 days
Secured Domestic Convertible Bonds [Member]
Disclosure of detailed information about borrowings [line items]
Secured domestic bonds conversion price \| $ / shares			$ 4.8
Notional Amount \| $			$ 250,000
USISH Bonds [Member]
Disclosure of detailed information about borrowings [line items]
Notional Amount				$ 404,026	$ 14,565
Effective interest rate on Contract				4.2989%	4.2989%	4.2989%
Aggregate fair value of the redemption option				$ 6,756	$ 244
USISH Bonds [Member] \| USISH [Member]
Disclosure of detailed information about borrowings [line items]
Borrowings maturity	Within 5 trading days after maturity
Borrowings, interest rate	108.00%
Borrowings	¥ 3,450,000
Notional Amount	¥ 100
Conversion Period of Bonds	9 months
Conversion Price \| ¥ / shares	¥ 20.25			$ 19.75
Percentage of current conversion price on Stock Exchange				80.00%	80.00%	80.00%
Percentage of par value on USISH Bonds				102.00%	102.00%	102.00%
USISH Bonds [Member] \| USISH [Member] \| Bottom of range [member]
Disclosure of detailed information about borrowings [line items]
Percentage of current conversion price on Stock Exchange				70.00%	70.00%	70.00%
Number of consecutive trading days for determining Conversion price				15 days
USISH Bonds [Member] \| USISH [Member] \| Top of range [member]
Disclosure of detailed information about borrowings [line items]
Number of consecutive trading days for determining Conversion price				30 days
USISH Bonds [Member] \| USIE and ASE (Shanghai) Inc [Member]
Disclosure of detailed information about borrowings [line items]
Borrowings	¥ 2,670,199
Unconverted USISH Bonds [Member] \| USISH [Member]
Disclosure of detailed information about borrowings [line items]
Borrowings						¥ 30,000
Percentage of current conversion price on Stock Exchange				130.00%	130.00%	130.00%
Unconverted USISH Bonds [Member] \| USISH [Member] \| Bottom of range [member]
Disclosure of detailed information about borrowings [line items]
Number of consecutive trading days for determining Conversion price				20 days
Unconverted USISH Bonds [Member] \| USISH [Member] \| Top of range [member]
Disclosure of detailed information about borrowings [line items]
Percentage of current conversion price on Stock Exchange				130.00%	130.00%	130.00%
Number of consecutive trading days for determining Conversion price				30 days