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, 2017				$ 150,000	$ 10,746	$ 1,733,348	$ 1,033,526	$ (26,736)	$ (39,308)
Common stock issued under employee plans					123				22,846
Common stock repurchased		$ (62,500)							(62,514)
Common stock issued for acquisitions					297	110,374
Unit amortization, net of forfeitures						77,350
Net income		279,906					279,906
Dividends declared, Common							(31,097)
Dividends declared, Preferred							(7,031)
Common stock issued under employee plans and related tax benefits						(52,922)	(9,774)
Other						8	1,130
Dividends declared to equity-award holders						5,074
Unrealized gains/(losses) on securities, net of tax		(28,065)	[1],[2],[3],[4]					(28,065)
Unrealized gains/(losses) on cash flow hedging activities, net of tax								1,895
Foreign currency translation adjustment, net of tax		(3,434)	[2],[4]					(3,433)
Cumulative adjustments for accounting changes	[5]						(1,124)	(3,050)
Balance, end of period at Sep. 30, 2018		3,161,569		150,000	11,166	1,873,232	1,265,536	(59,389)	(78,976)	$ 3,161,569
Balance, beginning of period at Jun. 30, 2018				150,000	10,869	1,736,853	1,175,151	(53,393)	(65,118)
Common stock issued under employee plans									2,773
Common stock repurchased		(16,600)							(16,631)
Common stock issued for acquisitions					297	110,374
Unit amortization, net of forfeitures						27,752
Net income		103,858					103,858
Dividends declared, Common							(10,524)
Dividends declared, Preferred							(2,343)
Common stock issued under employee plans and related tax benefits						(3,516)	(664)
Other						45	58
Dividends declared to equity-award holders						1,724
Unrealized gains/(losses) on securities, net of tax		(3,138)	[1],[2],[3],[4]					(3,138)
Unrealized gains/(losses) on cash flow hedging activities, net of tax								(1,523)
Foreign currency translation adjustment, net of tax		(1,336)	[2],[4]					(1,335)
Balance, end of period at Sep. 30, 2018		3,161,569		150,000	11,166	1,873,232	1,265,536	(59,389)	(78,976)	3,161,569
Balance, beginning of period at Dec. 31, 2018		3,197,593		150,000	11,166	1,893,304	1,366,503	(72,523)	(180,857)		$ 30,000
Common stock issued under employee plans									71,793
Common stock repurchased		(180,400)							(180,434)
Unit amortization, net of forfeitures						86,388
Net income		317,706					319,318				1,612
Dividends declared, Common							(38,249)
Dividends declared, Preferred							(12,476)
Common stock issued under employee plans and related tax benefits						(84,902)	(18,770)
Issuance of preferred stock				160,000		(5,012)
Other						37	(1,296)
Unrealized gains/(losses) on securities, net of tax		58,428	[1],[2],[3],[4]					58,428
Unrealized gains/(losses) on cash flow hedging activities, net of tax								(4,260)
Foreign currency translation adjustment, net of tax		(5,239)	[2],[4]					(5,239)
Cumulative adjustments for accounting changes	[5]						(11,204)
Capital contributions from non-controlling interest holders											26,800
Distributions to non-controlling interest holders											(2,379)
Balance, end of period at Sep. 30, 2019		3,557,748		310,000	11,166	1,889,815	1,603,826	(23,594)	(289,498)	3,501,715	56,033
Balance, beginning of period at Jun. 30, 2019				310,000	11,166	1,867,209	1,512,702	(35,355)	(236,596)		56,296
Common stock issued under employee plans									2,566
Common stock repurchased		(55,500)							(55,468)
Unit amortization, net of forfeitures						26,300
Net income		109,414					110,122				708
Dividends declared, Common							(12,572)
Dividends declared, Preferred							(4,844)
Common stock issued under employee plans and related tax benefits						(3,708)	(478)
Other						14	(709)
Unrealized gains/(losses) on securities, net of tax		16,344	[1],[2],[3],[4]					16,344
Unrealized gains/(losses) on cash flow hedging activities, net of tax								(477)
Foreign currency translation adjustment, net of tax		(4,106)	[2],[4]					(4,106)
Cumulative adjustments for accounting changes	[6]						(395)
Distributions to non-controlling interest holders											(971)
Balance, end of period at Sep. 30, 2019		$ 3,557,748		$ 310,000	$ 11,166	$ 1,889,815	$ 1,603,826	$ (23,594)	$ (289,498)	$ 3,501,715	$ 56,033

[1] As part of the adoption of ASU 2019-04, in the third quarter of 2019, the Company made a one-time election to transfer a portion of its held-to-maturity securities to available-for-sale. The transfer resulted in a net of tax increase to accumulated other comprehensive income of $17.9 million. See Notes 2 and 6 for additional information on the transfer.

[2] Net of tax expense of $4.4 million and tax benefit of $2.1 million for the three months ended September 30, 2019 and 2018, respectively. Net of tax expense of $18.1 million and tax benefit of $10.4 million for the nine months ended September 30, 2019 and 2018, respectively.

[3] Reclassifications to earnings during the three months ended September 30, 2019 were immaterial. Net of reclassifications to earnings of realized losses of $0.2 million for the nine months ended September 30, 2019. There were no reclassifications to earnings during the three and nine months ended September 30, 2018.

[4] The adoption of ASU 2018-02 on January 1, 2018 resulted in a reclassification of $3.0 million to retained earnings related to cash flow hedges and investment portfolio risk.

[5] ^{Cumulative adjustments for accounting changes relate to the adoption of certain accounting updates during 2019 and 2018. See Note 2 to the consolidated financial statements for further information. The 2018 adjustments are described further in Note 2 to the consolidated financial statements in our 2018 Form 10-K.}

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