STOCKHOLDERS' EQUITY STATEMENTS - USD ($) $ in Millions	Total	Common stock and paid-in capital	Retained earnings	Accumulated other comprehensive income (loss)
Balance, beginning of period at Jun. 30, 2016		$ 68,178	$ 13,118	$ 1,794
Common stock cash dividends	$ (3,024)
Balance, end of period at Sep. 30, 2016		67,747	12,757	1,958
Balance, beginning of period at Jun. 30, 2016		68,178	13,118	1,794
Common stock issued		372
Net income (loss)	11,934		11,934
Other comprehensive loss	(1,142)			(1,142)
Common stock cash dividends			(6,028)
Common stock repurchased		(1,935)	(6,024)
Stock-based compensation expense		1,470
Other, net		92
Balance, end of period at Dec. 31, 2016	81,829	68,177	13,000	652
Balance, beginning of period at Sep. 30, 2016		67,747	12,757	1,958
Common stock issued		131
Net income (loss)	6,267		6,267
Other comprehensive loss	(1,306)			(1,306)
Common stock cash dividends	(3,012)		(3,003)
Common stock repurchased		(561)	(3,021)
Stock-based compensation expense		767
Other, net		93
Balance, end of period at Dec. 31, 2016	81,829	68,177	13,000	652
Balance, beginning of period at Jun. 30, 2017	87,711	69,315	17,769	627
Common stock cash dividends	(3,238)
Balance, end of period at Sep. 30, 2017		69,419	19,702	526
Balance, beginning of period at Jun. 30, 2017	87,711	69,315	17,769	627
Common stock issued		496
Net income (loss)	274		274
Other comprehensive loss	(1,026)			(1,026)
Common stock cash dividends			(6,471)
Common stock repurchased		(1,577)	(3,005)
Stock-based compensation expense		1,959
Other, net		(1)
Balance, end of period at Dec. 31, 2017	78,360	70,192	8,567	(399)
Balance, beginning of period at Sep. 30, 2017		69,419	19,702	526
Common stock issued		189
Net income (loss)	(6,302)		(6,302)
Other comprehensive loss	(925)			(925)
Common stock cash dividends	(3,236)		(3,232)
Common stock repurchased		(402)	(1,601)
Stock-based compensation expense		986
Other, net		0
Balance, end of period at Dec. 31, 2017	$ 78,360	$ 70,192	$ 8,567	$ (399)