Consolidated Statements Of Changes In Shareholders' Equity - USD ($) $ in Thousands		Total		Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income/(Loss) [Member]	Treasury Stock at Cost [Member]	Parent [Member]	Non-controlling Interests [Member]
Balance, beginning of year at Dec. 31, 2015					$ 10,426	$ 1,820,772	$ 805,685	$ (39,533)	$ (104,934)
Common stock issued under employee plans									104,375
Common stock repurchased									(113,462)
Common stock issued for acquisitions						(723)			13,536
Unit amortization, net of forfeitures						189,746
Net income		$ 81,520					81,520
Dividends declared, Preferred							(3,906)
Common stock issued under employee plans and related tax benefits						(159,391)	(6,341)
Tax deficit from stock-based compensation	[1]					(4,904)
Issuance of preferred stock				$ 150,000		(4,949)
Unrealized gains/(losses) on securities, net of tax								5,803
Unrealized gains/(losses) on cash flow hedging activities, net of tax								7,288
Foreign currency translation adjustment, net of tax		(12,600)	[2],[3]					(12,600)
Balance, end of year at Dec. 31, 2016		2,738,408		150,000	10,426	1,840,551	876,958	(39,042)	(100,485)	$ 2,738,408
Common stock issued under employee plans					292				74,175
Common stock repurchased		(13,000)							(12,998)
Common stock issued for acquisitions					28	9,324
Unit amortization, net of forfeitures						167,908
Dividends declared to equity-award holders						3,758
Net income		182,871					182,871
Dividends declared, Common							(17,446)
Dividends declared, Preferred							(9,375)
Common stock issued under employee plans and related tax benefits						(288,152)
Other						(41)	518
Unrealized gains/(losses) on securities, net of tax								4,730
Unrealized gains/(losses) on cash flow hedging activities, net of tax								(320)
Foreign currency translation adjustment, net of tax		7,896	[2],[3]					7,896
Balance, end of year at Dec. 31, 2017		2,861,576		150,000	10,746	1,733,348	1,033,526	(26,736)	(39,308)	2,861,576
Common stock issued under employee plans					123				28,655
Common stock repurchased		(170,200)							(170,204)
Common stock issued for acquisitions					297	110,374
Unit amortization, net of forfeitures						102,971
Dividends declared to equity-award holders						6,812
Net income		393,968					393,968
Dividends declared, Common							(41,450)
Dividends declared, Preferred							(9,375)
Common stock issued under employee plans and related tax benefits						(60,256)	(10,985)
Other						55	1,943
Unrealized gains/(losses) on securities, net of tax								(36,254)
Unrealized gains/(losses) on cash flow hedging activities, net of tax								(792)
Foreign currency translation adjustment, net of tax		(5,691)	[2],[3]					(5,691)
Balance, end of year at Dec. 31, 2018		$ 3,197,593		$ 150,000	$ 11,166	$ 1,893,304	1,366,503	(72,523)	$ (180,857)	$ 3,167,593	$ 30,000
Non-controlling interests											$ 30,000
Cumulative effect of adoption of ASU | ASU 2014-09 [Member]							(4,174)
Cumulative effect of adoption of ASU | ASU 2018-02 [Member]							$ 3,050	$ (3,050)

[1] During the year ended December 31, 2017, we adopted new stock-based compensation guidance. See Note 2 of the Notes to Consolidated Financial Statements for additional information.

[2] Net of a tax benefit of $11.2 million and tax expenses of $3.3 million and $0.3 million for the years ended December 31, 2018, 2017, and 2016, respectively.

[3] The adoption of ASU 2018-02 on January 1, 2018 resulted in a reclassification of $3.1 million to retained earnings related to cash flow hedges and investment portfolio risk. The reclassification is reflected in the activity for the year ended December 31, 2018. See Note 2 for further details.