Consolidated Statement of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement Of Partners Capital [Abstract]
Net income	$ 526,091	$ 355,923	$ 1,371,861	$ 1,085,903
Other comprehensive income, net of tax and reclassification adjustments:
Net unrealized gains (losses) on investment securities	(30,381)	18,258	(167,798)	33,834
Cash flow hedges adjustments	(961)	(1,120)	(13,972)	(2,098)
Foreign currency translation adjustment	(265)	863	(1,409)	2,489
Defined benefit plans liability adjustments	7,149	4,165	21,447	12,496
Total other comprehensive income (loss)	(24,458)	22,166	(161,732)	46,721
Total comprehensive income	$ 501,633	$ 378,089	$ 1,210,129	$ 1,132,624

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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