Consolidated Statement of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement Of Partners Capital [Abstract]
Net income	$ 480,081	$ 526,091	$ 1,436,083	$ 1,371,861
Other comprehensive income (loss), net of tax and reclassification adjustments:
Net unrealized gains (losses) on investment securities	22,605	(30,381)	177,049	(167,798)
Cash flow hedges adjustments	8,695	(961)	155,666	(13,972)
Foreign currency translation adjustments	(1,704)	(265)	(2,104)	(1,409)
Defined benefit plans liability adjustments	3,054	7,149	9,162	21,447
Total other comprehensive income (loss)	32,650	(24,458)	339,773	(161,732)
Total comprehensive income	$ 512,731	$ 501,633	$ 1,775,856	$ 1,210,129

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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