Consolidated Statement of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Statement of Partners' Capital [Abstract]
Net income	$ 298,528	$ 241,613
Other comprehensive income, net of tax and reclassification adjustments:
Net unrealized gains on investment securities	97,194	25,339
Cash flow hedges adjustments	(24)	871
Foreign currency translation adjustment	(53)	(2,384)
Defined benefit plans liability adjustments	4,321	4,677
Total other comprehensive income	101,438	28,503
Total comprehensive income	$ 399,966	$ 270,116

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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