Shareholders' Equity - Additional Information (Details) - USD ($) shares in Millions	3 Months Ended
	Jun. 30, 2018	May 01, 2018	Apr. 30, 2018
Share Repurchase Program [Line Items]
Number of shares repurchased (in shares)	112.8
Amount of share repurchases	$ 20,000,000,000
$100 billion share repurchase program announced on May 1, 2018
Share Repurchase Program [Line Items]
Maximum amount authorized for repurchase of common stock		$ 100,000,000,000
Amount of share repurchases	9,600,000,000
$210 billion previous share repurchase program
Share Repurchase Program [Line Items]
Maximum amount authorized for repurchase of common stock			$ 210,000,000,000
Amount of share repurchases	$ 10,400,000,000