Borrowings and Subordinated Debentures Borrowings and Subordinated Debentures (Details 1) $ in Thousands, € in Millions		12 Months Ended
		Dec. 31, 2015 USD ($)	Dec. 31, 2015 EUR (€)	Dec. 31, 2014 USD ($)
Subordinated Borrowing [Line Items]
Subordinated debentures		$ 436,000		$ 433,583
Subordinated Debt Trust V Due September 2033 [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross		$ 10,310		$ 10,310
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		3.63%	3.63%	3.33%
Debt Instrument Date Issued		Aug. 15, 2003
Debt Instrument, Maturity Date		Sep. 17, 2033
Debt Instrument, Basis Spread on Variable Rate		3 month LIBOR + 3.10
Subordinated Debt Trust VI Due September 2033 [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross		$ 10,310		$ 10,310
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		3.39%	3.39%	3.29%
Debt Instrument Date Issued		Sep. 03, 2003
Debt Instrument, Maturity Date		Sep. 15, 2033
Debt Instrument, Basis Spread on Variable Rate		3 month LIBOR + 3.05
Subordinated Debt Trust CII Due September 2033 [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross		$ 5,155		$ 5,155
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		3.35%	3.35%	3.19%
Debt Instrument Date Issued		Sep. 17, 2003
Debt Instrument, Maturity Date		Sep. 17, 2033
Debt Instrument, Basis Spread on Variable Rate		3 month LIBOR + 2.95
Subordinated Debt Trust VII Due April 2034 [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross		$ 61,856		$ 61,856
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		3.07%	3.07%	2.98%
Debt Instrument Date Issued		Feb. 05, 2004
Debt Instrument, Maturity Date		Apr. 23, 2034
Debt Instrument, Basis Spread on Variable Rate		3 month LIBOR + 2.75
Subordinated Debt Trust CIII Due September 2035 [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross		$ 20,619		$ 20,619
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		2.20%	2.20%	1.93%
Debt Instrument Date Issued		Aug. 15, 2005
Debt Instrument, Maturity Date		Sep. 15, 2035
Debt Instrument, Basis Spread on Variable Rate		3 month LIBOR + 1.69
Subordinated Debt Trust FCCI Due March 2037 [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross		$ 16,495		$ 16,495
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		2.11%	2.11%	1.84%
Debt Instrument Date Issued		Jan. 25, 2007
Debt Instrument, Maturity Date		Mar. 15, 2037
Debt Instrument, Basis Spread on Variable Rate		3 month LIBOR + 1.60
Subordinated Debt Trust FCBI Due December 2035 [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross		$ 10,310		$ 10,310
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		2.06%	2.06%	1.79%
Debt Instrument Date Issued		Sep. 30, 2005
Debt Instrument, Maturity Date		Dec. 15, 2035
Debt Instrument, Basis Spread on Variable Rate		3 month LIBOR + 1.55
Trust Preferred Securities Two Thousand Five Series One [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross		$ 82,475		$ 82,475
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		2.46%	2.46%	2.19%
Debt Instrument Date Issued		Nov. 21, 2005
Debt Instrument, Maturity Date		Dec. 15, 2035
Debt Instrument, Basis Spread on Variable Rate		3 month LIBOR + 1.95
Trust Preferred Securities Two Thousand Five Series Two [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross		$ 128,866		$ 128,866
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		2.27%	2.27%	2.18%
Debt Instrument Date Issued		Dec. 14, 2005
Debt Instrument, Maturity Date		Jan. 30, 2036
Debt Instrument, Basis Spread on Variable Rate		3 month LIBOR + 1.95
Two Thousand Six One Term Debt Securitization [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross		$ 51,545		$ 51,545
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		2.27%	2.27%	2.18%
Debt Instrument Date Issued		Feb. 22, 2006
Debt Instrument, Maturity Date		Apr. 30, 2036
Debt Instrument, Basis Spread on Variable Rate		3 month LIBOR + 1.95
Two Thousand Six Two Term Debt Securitization [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross		$ 51,550		$ 51,550
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		2.27%	2.27%	2.18%
Debt Instrument Date Issued		Sep. 27, 2006
Debt Instrument, Maturity Date		Oct. 30, 2036
Debt Instrument, Basis Spread on Variable Rate		3 month LIBOR + 1.95
Trust Preferred Securities Two Thousand Six Series Three [Member]
Subordinated Borrowing [Line Items]
Liability, Reporting Currency Denominated, Value | €			€ 25.8
Long-term Debt, Gross	[1]	$ 28,007		$ 31,188
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		2.82%	2.82%	2.14%
Debt Instrument Date Issued		Sep. 29, 2006
Debt Instrument, Maturity Date		Oct. 30, 2036
Debt Instrument, Basis Spread on Variable Rate		3 month EURIBOR + 2.05
Trust Preferred Securities Two Thousand Six Series Four [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross		$ 16,470		$ 16,470
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		2.27%	2.27%	2.18%
Debt Instrument Date Issued		Dec. 05, 2006
Debt Instrument, Maturity Date		Jan. 30, 2037
Debt Instrument, Basis Spread on Variable Rate		3 month LIBOR + 1.95
Trust Preferred Securities Two Thousand Six Series Five [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross		$ 6,650		$ 6,650
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		2.27%	2.27%	2.18%
Debt Instrument Date Issued		Dec. 19, 2006
Debt Instrument, Maturity Date		Jan. 30, 2037
Debt Instrument, Basis Spread on Variable Rate		3 month LIBOR + 1.95
Two Thousand Seven One Term Debt Securitization [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross		$ 39,177		$ 39,177
Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate		2.27%	2.27%	2.18%
Debt Instrument Date Issued		Jun. 13, 2007
Debt Instrument, Maturity Date		Jul. 30, 2037
Debt Instrument, Basis Spread on Variable Rate		3 month LIBOR + 1.95
Subordinated Debt [Member]
Subordinated Borrowing [Line Items]
Long-term Debt, Gross		$ 539,795		$ 542,976
Debt Instrument, Unamortized Discount	[2]	(103,795)		(109,393)
Subordinated debentures		$ 436,000		$ 433,583

[1] Denomination is in Euros with a value of €25.8 million

[2] Amount represents the fair value adjustment on trust preferred securities assumed in acquisitions.