Equity (Tables)

12 Months Ended

Dec. 31, 2017

Disclosure of classes of share capital [Line Items]

Common stocks

	December 31
	2016		2017
	NT$		NT$
	(In Millions)
Number of authorized shares		12,000		12,000
Authorized shares	$	120,000	$	120,000
Number of issued and paid shares		7,757		7,757
Issued and outstanding shares	$	77,574	$	77,574

Adjustments of Additional Paid-in Capital

The adjustments of additional paid-in capital for the years ended December 31, 2015, 2016 and 2017 were as follows:

	Share Premium		Movements of Additional Paid-in Capital for Associates and Joint Ventures Accounted for Using Equity Method		Movements of Additional Paid-in Capital Arising from Changes in Equities of Subsidiaries			Difference between Consideration Received and Carrying Amount of the Subsidiaries’ Net Assets upon Disposal		Donated Capital		Stockholders’ Contribution Due to Privatization		Total
	NT$		NT$		NT$			NT$		NT$		NT$		NT$
	(In Millions)
Balance on January 1, 2015	$	126,045	$	—	$	14		$	—	$	13	$	20,648	$	146,720
Partial disposal of interests in subsidiaries		—		—		—			27		—		—		27
Other changes in additional paid-in capital in subsidiaries		—		—		1			—		—		—		1
Subsidiary purchased its treasury stock		—		—		(15	)		—		—		—		(15	)
Balance on December 31, 2015	$	126,045	$	—	$	—		$	27	$	13	$	20,648	$	146,733
Balance on January 1, 2016	$	126,045	$	—	$	—		$	27	$	13	$	20,648	$	146,733
Partial disposal of interests in subsidiaries		—		—		—			58		—		—		58
Change in additional paid-in capital for not participating in the capital increase of a subsidiary		—		—		389			—		—		—		389
Share-based payment transactions of subsidiaries		—		—		—			—		—		—		—
Balance on December 31, 2016	$	126,045	$	—	$	389		$	85	$	13	$	20,648	$	147,180
Balance on January 1, 2017	$	126,045	$	—	$	389		$	85	$	13	$	20,648	$	147,180
Unclaimed dividend		—		—		—			—		3		—		3
Change in additional paid-in capital from investments in associates and joint ventures accounted for using equity method		—		—		—			—		—		—		—
Partial disposal of interests in subsidiaries		—		—		1			76		—		—		77
Change in additional paid-in capital for not participating in the capital increase of a subsidiary		—		—		802			—		—		—		802
Other changes in additional paid-in capital in subsidiaries		—		—		—			—		—		—		—
Share-based payment transactions of subsidiaries		—		—		2			—		—		—		2
Treasury stock transfer of subsidiaries		—		—		27			—		—		—		27
Balance on December 31, 2017	$	126,045	$	—	$	1,221		$	161	$	16	$	20,648	$	148,091

Appropriations of Earnings

The appropriations of the 2015 and 2016 earnings of Chunghwa approved by the stockholders in their meetings on June 24, 2016 and June 23, 2017 were as follows:

	Appropriation of Earnings				Dividends Per Share
	For Fiscal Year 2015		For Fiscal Year 2016		For Fiscal Year 2015		For Fiscal Year 2016
	NT$		NT$		NT$		NT$
	(In Millions)
Special reserve	$	—	$	5
Cash dividends		42,551		38,336	$	5.4852	$	4.9419

	For Fiscal Year 2017
	Appropriation of Earnings		Dividends Per Share
	NT$		NT$
	(In Millions)
Reversal of special reserve	$	5
Cash dividends		37,205	$	4.796

Noncontrolling Interests

Noncontrolling interests

	Year Ended December 31
	2015			2016			2017
	NT$			NT$			NT$
	(In Millions)
Beginning balance	$	4,924		$	5,065		$	6,272
Attributable to noncontrolling interests
Net income for the year		813			1,141			1,172
Exchange differences arising from the translation of the foreign operations		(3	)		(41	)		(12	)
Unrealized gain (loss) on available-for-sale financial assets		2			—			(2	)
Income tax relating to unrealized gain and loss on available-for-sale financial assets		—			—			1
Remeasurements of defined benefit pension plans		(3	)		(18	)		(8	)
Income tax relating to remeasurements of defined benefit pension plans		1			3			—
Share of other comprehensive income (loss) of associates accounted for using equity method		2			(1	)		(2	)
Cash dividends distributed by subsidiaries		(350	)		(710	)		(942	)
Partial disposal of interests in subsidiaries		18			25			29
Change in additional paid-in capital for not participating in the capital increase of a subsidiary		—			786			1,750
Other changes in additional paid-in capital of subsidiaries		2			—			—
Share-based payment transactions of subsidiaries		36			17			20
Subsidiary purchased its treasury stock		(416	)		—			—
Net increase in noncontrolling interests		39			5			196
Ending balance	$	5,065		$	6,272		$	8,474

Unrealized gain (loss) on available-for-sale financial assets [Member]

Disclosure of classes of share capital [Line Items]

Unrealized Gain (Loss) on Available-for-sale Financial Assets

Unrealized gain (loss) on available-for-sale financial assets

	Year Ended December 31
	2015			2016			2017
	NT$			NT$			NT$
	(In Millions)
Beginning balance	$	740		$	91		$	(51	)
Unrealized gain (loss) on available-for-sale financial assets		(670	)		(721	)		607
Income tax relating to unrealized gain and loss on available-for-sale financial assets		(2	)		2			2
Amount reclassified from equity to profit or loss on disposal of available-for-sale financial assets		—			—			—
Amount reclassified from equity to profit or loss on impairment of available-for-sale financial assets		23			577			—
Ending balance	$	91		$	(51	)	$	558