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Short-term Bills Payable - Summary of Annual Interest Rates of Commercial Paper Payable (Detail)	Dec. 31, 2020
Bottom of Range [Member]
Short Term Bills Payable [Line Items]
Commercial paper payable	0.34%
Top of Range [Member]
Short Term Bills Payable [Line Items]
Commercial paper payable	0.36%

X

- Definition

Annual interest rates of commercial paper payable.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

X

- Definition

Short-term bills payable.

+ References

No definition available.

+ Details

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

X

- Details

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Data Type:	na
Balance Type:
Period Type:

X

- Details

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Data Type:	na
Balance Type:
Period Type: