Equity Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended																12 Months Ended
	Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2012		Sep. 30, 2012		Jun. 30, 2012		Mar. 31, 2012		Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Components of Other Comprehensive Income [Line Items]
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax																	$ (11,797)		$ (1,577)		$ 5,987
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax																	(4,656)		(640)		2,261
Unrealized gain/ (loss) on securities available for sale																	(7,141)		(937)		3,726
Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, before Tax																	49		871		798
Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, Tax																	21		314		308
Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, Net of Tax																	(28)		(557)		(490)
Other Comprehensive Income (Loss) Available-for-Sale Securities Adjustment due to Discontinued Operations, before Tax																			(35)
Other Comprehensive Income (Loss) Available-for-Sale Securities Adjustment due to Discontinued Operations, Tax																			(12)
Reclassification due to sale of discontinued operation																	0		23		0
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax																	(11,846)		(2,413)		5,189
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax																	(4,677)		(942)		1,953
Net unrealized gain/ (loss) on securities available for sale																	(7,169)		(1,471)		3,236
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax																	15		(1,638)		(4,838)
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax																	13		(760)		(2,008)
Unrealized gain/ (loss) on cash flow hedges																	2		(878)		(2,830)
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, before Tax																	2,083		1,757		1,872
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Tax																	879		742		777
Other Comprehensive Income (Loss), Reclassification Adjustment on Derivatives Included in Net Income, Net of Tax																	1,204		1,015		1,095
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, before Tax																	2,098		119		(2,966)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax																	892		(18)		(1,231)
Net unrealized gain/ (loss) on cash flow hedges																	1,206		137		(1,735)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Reclassification Adjustments and Tax																					78
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, before Reclassification Adjustments, Tax																					30
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Reclassification Adjustments, Net of Tax																					48
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, before Tax																					(1,074)
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, Tax																					(377)
Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, Net of Tax																					(697)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, before Tax, Portion Attributable to Parent																	(652)		(216)		1,152
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Tax																	(294)		(80)		407
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax																	(358)		(136)		745
Other Comprehensive Income (Loss), before Tax																	(10,400)		(2,510)		3,375
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent																	(4,079)		(1,040)		1,129
Other comprehensive income/ (loss), net of tax																	(6,321)		(1,470)		2,246
Net Income Attributable to the Parent Before Tax																	102,843	[1]	73,601	[1]	53,417	[1]
Income tax expense/(benefit)	7,303	[2]	8,557	[2]	10,551	[2]	5,897	[2]	6,115	[2]	5,124	[2]	5,240	[2]	3,851	[2]	32,308	[3]	20,330	[3]	14,280	[3]
Net income attributable to the Company	17,668	[2]	18,336	[2]	21,328	[2]	13,203	[2]	13,092	[2]	16,513	[2]	14,161	[2]	9,505	[2]	70,535		53,271		39,137
Comprehensive Income (Loss), Before Tax, Attributable to Parent																	92,443		71,091		56,792
Comprehensive Income (Loss), Tax, Attributable to Parent																	28,229		19,290		15,409
Total comprehensive income attributable to the Company, net																	$ 64,214		$ 51,801		$ 41,383

[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 2013, 2012, and 2011 are not consistent due to 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 2013, 2012, and 2011. See Part II. Item 8. “Financial Statements and Supplementary Data - Note 17: Income Taxes” for additional details.