Consolidated Statement of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Statement Of Partners Capital [Abstract]
Net income	$ 348,927	$ 298,528
Other comprehensive income, net of tax and reclassification adjustments:
Net unrealized gains (losses) on investment securities	(1,356)	97,194
Cash flow hedges adjustments	(23)	(24)
Foreign currency translation adjustment	476	(53)
Defined benefit plans liability adjustments	3,972	4,321
Total other comprehensive income	3,069	101,438
Total comprehensive income	$ 351,996	$ 399,966

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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