Condensed Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Millions	Total	GIA Common Units	Retained Earnings	Treasury Stock, Common	Accumulated Other Comprehensive Income/(Loss)	Noncontrolling Interest
Common shares in treasury				76,000
Balance at beginning of period (in shares) at Jun. 30, 2023		327,000
Balance at beginning of period at Jun. 30, 2023	$ (2,957)	$ 2,746	$ (642)		$ (151)	$ 1
Treasury, balance at beginning of period (in shares) at Jun. 30, 2023				(76,000)
Treasury, balance at beginning of period at Jun. 30, 2023	(4,911)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	620					3
Net Income (Loss) Attributable to Parent	617
Other Comprehensive Income (Loss), Net of Tax	(9)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(9)				(9)
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture		0		1,000
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	118	$ 41		$ 77
Purchase of treasury shares, net	(750)	$ (100)
Treasury shares acquired (in shares)				(9,000)
Dividends	(372)		(372)
Stockholders' Equity, Other Shares				(1,000)
Other	0		1			1
Balance at end of period (in shares) at Mar. 31, 2024		327,000
Balance at end of period at Mar. 31, 2024	(3,359)	$ 2,887	(396)		(160)	3
Treasury, balance at end of period (in shares) at Mar. 31, 2024				(83,000)
Treasury, balance at end of period at Mar. 31, 2024	(5,693)
Treasury Stock, Value, Acquired, Cost Method	(759)			$ (859)
Common shares in treasury				83,000
Balance at beginning of period (in shares) at Dec. 31, 2023		327,000
Balance at beginning of period at Dec. 31, 2023	(3,547)	$ 2,855	(535)		(155)	2
Treasury, balance at beginning of period (in shares) at Dec. 31, 2023				(83,000)
Treasury, balance at beginning of period at Dec. 31, 2023	(5,714)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	262					1
Net Income (Loss) Attributable to Parent	261
Other Comprehensive Income (Loss), Net of Tax	(5)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(5)				(5)
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture		0		0
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	53	$ 32		$ 21
Dividends	(123)		(123)
Stockholders' Equity, Other Shares
Other	(1)		1
Balance at end of period (in shares) at Mar. 31, 2024		327,000
Balance at end of period at Mar. 31, 2024	(3,359)	$ 2,887	(396)		(160)	3
Treasury, balance at end of period (in shares) at Mar. 31, 2024				(83,000)
Treasury, balance at end of period at Mar. 31, 2024	$ (5,693)
Common shares in treasury				83,000
Common shares in treasury	83,000			(83,000)
Balance at beginning of period (in shares) at Jun. 30, 2024	327,000	327,000
Balance at beginning of period at Jun. 30, 2024	$ (3,212)	$ 2,917	(286)		(167)	1
Treasury, balance at beginning of period (in shares) at Jun. 30, 2024	(83,000)			83,000
Treasury, balance at beginning of period at Jun. 30, 2024	$ (5,677)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	1,326					4
Net Income (Loss) Attributable to Parent	1,322
Other Comprehensive Income (Loss), Net of Tax	(9)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(9)				(9)
Noncontrolling Interest, Increase from Business Combination	$ 1,035					1,035
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture	1,000	0
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	$ 80	$ 28		$ 52
Purchase of treasury shares, net	$ (765)			$ (750)
Treasury shares acquired (in shares)				(6,000)
Retirement of treasury stock	0	(56,000)		(56,000)
Dividends	$ (370)		(370)
Payments to Noncontrolling Interests	7					7
Stockholders' Equity, Other Shares		(1,000)
Other	$ 1		2			0
Balance at end of period (in shares) at Mar. 31, 2025	271,000	271,000
Balance at end of period at Mar. 31, 2025	$ (1,898)	$ 2,946	664		(176)	1,050
Treasury, balance at end of period (in shares) at Mar. 31, 2025	(32,000)			(32,000)
Treasury, balance at end of period at Mar. 31, 2025	$ (6,382)
Treasury Stock, Value, Acquired, Cost Method	(757)			$ (757)
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested	17					17
Common shares in treasury				(29,000)
Balance at beginning of period (in shares) at Dec. 31, 2024		271,000
Balance at beginning of period at Dec. 31, 2024	(2,921)	$ 2,932	283		(180)	70
Treasury, balance at beginning of period (in shares) at Dec. 31, 2024				29,000
Treasury, balance at beginning of period at Dec. 31, 2024	(6,026)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	508					2
Net Income (Loss) Attributable to Parent	506
Other Comprehensive Income (Loss), Net of Tax	4
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	4
Noncontrolling Interest, Increase from Business Combination	963					963
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture		0		0
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture	35	$ 13		$ 22
Purchase of treasury shares, net
Treasury shares acquired (in shares)				(3,000)
Retirement of treasury stock				(56,000)
Dividends	(123)		(123)
Payments to Noncontrolling Interests	3					3
Stockholders' Equity, Other Shares
Other	$ 0	$ 1	(2)			1
Balance at end of period (in shares) at Mar. 31, 2025	271,000	271,000
Balance at end of period at Mar. 31, 2025	$ (1,898)	$ 2,946	$ 664		$ (176)	1,050
Treasury, balance at end of period (in shares) at Mar. 31, 2025	(32,000)			(32,000)
Treasury, balance at end of period at Mar. 31, 2025	$ (6,382)
Treasury Stock, Value, Acquired, Cost Method	(378)			$ (378)
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested	$ 17					$ 17
Common shares in treasury	32,000			32,000