Consolidated Statements Of Shareholders' Equity (Unaudited) - USD ($) $ in Thousands		Total		Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Treasury Stock at Cost [Member]	Parent [Member]	Non-controlling Interests [Member]
Balance, beginning of period at Dec. 31, 2018				$ 150,000	$ 11,166	$ 1,893,304	$ 1,366,503	$ (72,523)	$ (180,857)		$ 30,000
Common stock issued under employee plans						(95,295)	27		66,302
Common stock repurchased		$ (53,900)							(53,869)
Unit amortization, net of forfeitures						33,317
Net income		99,207					99,439
Dividends declared, Common							(12,944)
Dividends declared, Preferred							(2,344)
Issuance of preferred stock				160,000		(4,706)
Unrealized gains/(losses) on securities, net of tax		25,800	[1],[2]					25,800
Unrealized gains/(losses) on cash flow hedging activities, net of tax								(1,826)
Foreign currency translation adjustment, net of tax		2,168	[1]					2,168
Cumulative adjustments for accounting changes	[3]						(6,759)
Other						(16)	(264)
Capital contributions from non-controlling interest holders											26,800
Distributions to non-controlling interest holders											(458)
Deconsolidation of non-controlling interest											232
Balance, end of period at Mar. 31, 2019		3,433,197		310,000	11,166	1,826,604	1,443,658	(46,381)	(168,424)	$ 3,376,623	56,574
Balance, beginning of period at Dec. 31, 2019		3,669,790		310,000	11,166	1,909,286	1,715,704	(11,705)	(319,660)		54,999
Common stock issued under employee plans						(105,570)	(46,717)		54,579
Common stock repurchased		(56,200)							(56,160)
Unit amortization, net of forfeitures						33,799
Net income		86,589					86,589
Dividends declared, Common							(14,916)
Dividends declared, Preferred							(4,844)
Dividends declared to equity-award holders						350
Unrealized gains/(losses) on securities, net of tax		(73,227)	[1],[2]					(73,227)
Unrealized gains/(losses) on cash flow hedging activities, net of tax								(1,706)
Foreign currency translation adjustment, net of tax		(9,822)	[1]					(9,822)
Cumulative adjustments for accounting changes	[3]						(7,772)
Other						85	867
Deconsolidation of non-controlling interest											$ (54,999)
Balance, end of period at Mar. 31, 2020		$ 3,470,326		$ 310,000	$ 11,166	$ 1,837,950	$ 1,728,911	$ (96,460)	$ (321,241)	$ 3,470,326

[1] Net of a tax benefit of $27.9 million and tax expense of $10.1 million for the three months ended March 31, 2020 and 2019, respectively.

[2] Net of reclassifications to earnings of realized losses of $0.5 million during the three months ended March 31, 2020. There were no reclassifications to earnings during the three months ended March 31, 2019.

[3] Cumulative adjustments for accounting changes relate to the adoption of certain accounting updates during 2020 and 2019. See Note 2 to the consolidated financial statements for further information.