Equity - Narrative (Details) $ / shares in Units, $ in Millions		12 Months Ended
	Oct. 27, 2016 USD ($) shares	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	Sep. 30, 2017 USD ($)	Jan. 31, 2017 shares	Aug. 31, 2016 USD ($)
Class of Stock [Line Items]
Business combination related costs		$ 135	$ 123	$ 111
Allocation of recognized period costs, capitalized amount		$ 18	13	11
Excess tax benefit from share-based compensation, operating activities			15
Tax benefits from stock option plans				19
Capital shares reserved for future issuance (in shares) | shares		39,700,000
Number of options, exercised (in shares) | shares		2,989,950
Weighted average exercise price (in dollars per share) | $ / shares		$ 36.36
Vested in period, fair value		$ 206	$ 130	$ 96
Payments relating to treasury shares (in shares) | shares		1,503,453	1,074,162	979,295
Stock split, conversion ratio	5
Treasury stock, shares, retired (in shares) | shares	35,273,515
Treasury shares retired in connection with formation of ICE Group	$ 1,500
Repurchases of common stock (in shares) | shares		14,966,616	902,920	14,343,845
Repurchases of common stock		$ 949	$ 50	$ 660
Stock repurchase program, authorized amount					$ 1,200		$ 1,000
Employee Stock Option
Class of Stock [Line Items]
Award vesting period		3 years
Awards exercise period		10 years
Intrinsic value		$ 22	$ 18	$ 22
Compensation cost not yet recognized		$ 8
Compensation cost not yet recognized, Period for recognition		1 year 8 months 6 days
Number of options, exercised (in shares) | shares		2,989,950	2,787,525	2,699,865
Weighted average exercise price (in dollars per share) | $ / shares		$ 36.36	$ 31.61	$ 27.87
Employee Stock Option | Minimum
Class of Stock [Line Items]
Stock Options granted, expiration period		14 days
Employee Stock Option | Maximum
Class of Stock [Line Items]
Stock Options granted, expiration period		60 days
Time Based And Performance Based Restricted Stock
Class of Stock [Line Items]
Compensation cost not yet recognized		$ 142
Compensation cost not yet recognized, Period for recognition		1 year 3 months 19 days
Options, grants in period (in shares) | shares		3,274,358	3,251,017	3,457,590
Time Based Restricted Units
Class of Stock [Line Items]
Options, grants in period (in shares) | shares		2,364,288	2,325,985	1,871,785
Typical vesting period		3 years
Performance Based Restricted Stock Units
Class of Stock [Line Items]
Options, grants in period (in shares) | shares		767,109
Stock granted, value, net of forfeitures		$ 43
Typical vesting period		3 years
Stock-based compensation		$ 26
Performance Based Restricted Stock Units | Maximum | Restricted Stock
Class of Stock [Line Items]
Shares reserved for future issuance (in shares) | shares						1,534,218
Additional Paid-in Capital
Class of Stock [Line Items]
Treasury shares retired in connection with formation of ICE Group	1,100
Retained Earnings
Class of Stock [Line Items]
Treasury shares retired in connection with formation of ICE Group	$ 370