Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Millions		Total		Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests
Balance, beginning at Dec. 31, 2017		$ 18,355		$ 148	$ 8,197	$ 10,936	$ (1,026)	$ 100
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		796				816		(20)
Other comprehensive income (loss), net of tax		(308)					(308)
Compensation—restricted stock units		(21)			(18)	(3)	(21)
Other	[1]	0			(21)		21	0
Net change		467			(39)	813	(287)	(20)
Balance, ending at Sep. 30, 2018		18,822		148	8,158	11,749	(1,313)	80
Balance, beginning at Jun. 30, 2018		18,547		148	8,155	11,444	(1,285)	85
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		300	[2]			306		(6)
Other comprehensive income (loss), net of tax		(28)					(28)
Compensation—restricted stock units		2			3	(1)
Other		1				0		1
Net change		275			3	305	(28)	(5)
Balance, ending at Sep. 30, 2018		18,822		148	8,158	11,749	(1,313)	80
Balance, beginning at Dec. 31, 2018		16,580		132	8,176	9,524	(1,324)	72
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		(1,001)				(989)		(12)
Other comprehensive income (loss), net of tax		501					501
Compensation—restricted stock units		(3)			0	(3)
Other		23			20	5	0	(2)
Net change		(480)			20	(987)	501	(14)
Balance, ending at Sep. 30, 2019		16,100		132	8,196	8,537	(823)	58
Balance, beginning at Jun. 30, 2019		17,329		132	8,157	9,910	(933)	63
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)		(1,376)	[2]			(1,372)		(4)
Other comprehensive income (loss), net of tax		110					110
Compensation—restricted stock units		18			19	(1)
Other		19			20	0		(1)
Net change		(1,229)			39	(1,373)	110	(5)
Balance, ending at Sep. 30, 2019		$ 16,100		$ 132	$ 8,196	$ 8,537	$ (823)	$ 58

[1] .

[2] As of and for the Three Months Ended September 30, 2019:(Dollars in millions) Regional Bank Global Corporate & Investment Banking - U.S. Transaction Banking MUSA Other MUFG Americas Holdings CorporationResults of operations Net interest income $582 $104 $61 $39 $(32) $754Noninterest income 127 87 14 111 378 717Total revenue 709 191 75 150 346 1,471Noninterest expense 532 116 59 119 1,944 2,770(Reversal of) provision for credit losses 72 24 — — (1) 95Income (loss) before income taxes and including noncontrolling interests 105 511631 (1,597)(1,394)Income tax expense (benefit) (1) 19 (5) 10 7 (49) (18)Net income (loss) including noncontrolling interests 86 56 6 24 (1,548) (1,376)Deduct: net (income) loss from noncontrolling interests — — — — 4 4Net income (loss) attributable to MUAH $86 $56 $6 $24 $(1,544) $(1,372) Total assets, end of period $75,446 $20,820 $971 $35,199 $40,797 $173,233