Consolidated Statement of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement Of Partners Capital [Abstract]
Net income	$ 482,742	$ 352,610
Other comprehensive income (loss), net of tax and reclassification adjustments:
Net unrealized gains (losses) on investment securities	84,591	(100,684)
Cash flow hedges adjustments	44,921	(10,442)
Foreign currency translation adjustment	275	1,290
Defined benefit plans liability adjustments	2,285	7,260
Total other comprehensive income (loss)	132,072	(102,576)
Total comprehensive income	$ 614,814	$ 250,034

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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