Equity Other Comprehensive Income (Details) - USD ($) $ in Thousands		3 Months Ended																12 Months Ended
		Dec. 31, 2017	[2]	Sep. 30, 2017	[2]	Jun. 30, 2017	[2]	Mar. 31, 2017	[2]	Dec. 31, 2016	[2]	Sep. 30, 2016	[2]	Jun. 30, 2016	[2]	Mar. 31, 2016	[2]	Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax, [Abstract]
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax																		$ 7,782		$ (18,913)		$ (2,494)
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax																		3,063		(7,555)		(1,145)
Unrealized gain/ (loss) on securities available-for-sale																		4,719		(11,358)		(1,349)
Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, before Tax																		376		521		236
Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, Tax																		154		190		97
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax																		(222)		(331)		(139)
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax																		7,406		(19,434)		(2,730)
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax																		2,909		(7,745)		(1,242)
Net unrealized gain/ (loss) on securities available-for-sale																		4,497		(11,689)		(1,488)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax [Abstract]
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax																		325		(793)		(2,642)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax																		135		(332)		(1,088)
Unrealized gain/ (loss) on cash flow hedges																		190		(461)		(1,554)
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, before Tax																		1,179		1,666		4,052
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Tax																		491		687		1,698
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Net of Tax																		688		979		2,354
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax																		1,504		873		1,410
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax																		626		355		610
Net unrealized gain/ (loss) on cash flow hedges																		878		518		800
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax [Abstract]
Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment and Tax																		84		200		(193)
Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment, Tax																		34		77		(78)
Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment, after Tax																		50		123		(115)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax, Portion Attributable to Parent																		84		200		(193)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Tax																		34		77		(78)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax																		50		123		(115)
Other Comprehensive Income (Loss), before Tax																		8,994		(18,361)		(1,513)
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent																		3,569		(7,313)		(710)
Other comprehensive income/ (loss), net																		5,425		(11,048)		(803)
Net Income Attributable to the Parent Before Tax	[1]																	86,787		102,591		95,317
Income tax expense/(benefit)		$ 21,391		$ 8,289		$ 9,963		$ 6,553		$ 7,247		$ 8,652		$ 7,626		$ 7,438		46,196	[3]	30,963	[3]	30,392	[3]
Net income attributable to the Company		$ (18,280)		$ 19,803		$ 23,406		$ 15,662		$ 17,552		$ 19,636		$ 16,398		$ 18,041		40,591		71,628		64,925
Comprehensive Income (Loss), Before Tax, Attributable to Parent																		95,781		84,230		93,804
Comprehensive Income (Loss), Tax, Attributable to Parent																		49,765		23,650		29,682
Total comprehensive income attributable to the Company, net																		$ 46,016		$ 60,580		$ 64,122

[1] Pre-tax net income attributable to the Company is calculated as income before income taxes, plus net income from discontinued operations, less net income attributable to noncontrolling interests.

[2] Due to rounding, the sum of the four quarters may not add to the year to date total.

[3] The Company’s effective tax rate for 2017, 2016, and 2015 is not consistent due to the re-measurement of the deferred tax assets, impairment of goodwill not deductible for tax purposes, earnings from tax-exempt investments, non-deductible compensation, state and local taxes, income tax credits and income attributable to noncontrolling interests having a different impact on the effective tax rate due primarily to the different levels of income before taxes in years 2017, 2016, and 2015. See Part II. Item 8. “Financial Statements and Supplementary Data - Note 17: Income Taxes” for additional details.