Fair Value Measurements, Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	$ 1,675,212		$ 1,956,923
Investment securities	304,224		355,187
Available for sale securities	11,024,551		8,857,120
Fair value option securities	1,816,398		283,235
Residential mortgage loans held for sale	282,487		149,221
Loans	22,285,367		21,656,730
Allowance for loan losses	(204,432)	$ (202,534)	(207,457)	$ (210,569)	$ (215,142)	$ (230,682)
Loans, net of allowance	22,080,935		21,449,273
Mortgage servicing rights	193,661	208,308	259,254	284,673	278,719	252,867
Derviative contracts, net of cash collateral, Assets, Fair value	352,019		320,929
Time deposits	2,243,541		2,113,380
Subordinated debentures	275,909		275,913
Derivative contracts, net of cash collateral, Liabilities, Fair Value	336,791		362,306
Commercial [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	14,424,625		13,636,078
Allowance for loan losses	(106,643)	(106,397)	(102,226)	(104,098)	(113,722)	(124,269)
Commercial real estate [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	4,626,057		4,764,813
Allowance for loan losses	(54,350)	(54,188)	(60,026)	(60,189)	(58,758)	(56,621)
Residential mortgage [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	2,117,303		2,230,033
Allowance for loan losses	(15,534)	(15,724)	(17,964)	(18,683)	(18,544)	(18,451)
Personal [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	1,117,382		1,025,806
Allowance for loan losses	(10,150)	$ (9,388)	(9,473)	$ (8,709)	$ (8,646)	$ (9,124)
U.S. government agency debentures [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	63,334		63,765
Residential agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	1,480,458		1,791,584
Investment securities	11,125		12,612
Available for sale securities	7,740,461		5,804,708
Fair value option securities	1,263,862		283,235
Municipal and other tax-exempt securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	44,105		34,507
Investment securities	104,418		137,296
Available for sale securities	1,848		2,864
U.S. Treasury [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	2,296		493
Fair value option securities	552,536		0
Residential non-agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	44,803		59,736
Commercial agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	3,234,671		2,953,889
Other debt securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	50,387		24,411
Investment securities	188,681		205,279
Available for sale securities	472		35,430
Carrying (Reported) Amount, Fair Value Disclosure [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	761,130		741,749
Interest-bearing cash and cash equivalents	465,458		401,675
Trading securities	1,675,212		1,956,923
Investment securities	304,224		355,187
Available for sale securities	11,024,551		8,857,120
Fair value option securities	1,816,398
Residential mortgage loans held for sale	282,487		149,221
Loans	22,285,367		21,656,730
Allowance for loan losses	(204,432)		(207,457)
Loans, net of allowance	22,080,935		21,449,273
Mortgage servicing rights	193,661		259,254
Derviative contracts, net of cash collateral, Assets, Fair value	352,019		320,929
Deposits with no stated maturity	23,923,535		23,150,383
Time deposits	2,243,541		2,113,380
Other borrowed funds	10,235,385		7,142,801
Subordinated debentures	275,909		275,913
Derivative contracts, net of cash collateral, Liabilities, Fair Value	336,791		362,306
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Commercial [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	14,424,625		13,636,078
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Commercial real estate [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	4,626,057		4,764,813
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Residential mortgage [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	2,117,303		2,230,033
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Personal [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	1,117,382		1,025,806
Carrying (Reported) Amount, Fair Value Disclosure [Member] | U.S. government agency debentures [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	63,334		63,765
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Residential agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	1,480,458		1,791,584
Investment securities	11,125		12,612
Available for sale securities	7,740,461		5,804,708
Fair value option securities	1,263,862		283,235
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Municipal and other tax-exempt securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	44,105		34,507
Investment securities	104,418		137,296
Available for sale securities	1,848		2,864
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	36,928		42,656
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Other trading securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	50,387		24,411
Carrying (Reported) Amount, Fair Value Disclosure [Member] | U.S. Treasury [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	2,296		493
Fair value option securities	552,536
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Residential non-agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	44,803		59,736
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Commercial agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	3,234,671		2,953,889
Carrying (Reported) Amount, Fair Value Disclosure [Member] | Other debt securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	188,681		205,279
Available for sale securities	472		35,430
Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	761,130		741,749
Interest-bearing cash and cash equivalents	465,458		401,675
Trading securities	1,675,212		1,956,923
Investment securities	324,021		367,298
Available for sale securities	11,024,551		8,857,120
Fair value option securities	1,816,398
Residential mortgage loans held for sale	282,487		149,221
Loans	22,265,792		21,478,228
Allowance for loan losses	0		0
Loans, net of allowance	22,265,792		21,478,228
Mortgage servicing rights	193,661		259,254
Derviative contracts, net of cash collateral, Assets, Fair value	352,019		320,929
Deposits with no stated maturity	23,923,535		23,150,383
Time deposits	2,241,778		2,073,538
Other borrowed funds	10,193,602		7,071,953
Subordinated debentures	276,393		261,977
Derivative contracts, net of cash collateral, Liabilities, Fair Value	336,791		362,306
Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	14,397,846		13,526,162
Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial real estate [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	4,626,804		4,713,747
Estimate of Fair Value, Fair Value Disclosure [Member] | Residential mortgage [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	2,132,158		2,213,951
Estimate of Fair Value, Fair Value Disclosure [Member] | Personal [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	1,108,984		1,024,368
Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. government agency debentures [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	63,334		63,765
Estimate of Fair Value, Fair Value Disclosure [Member] | Residential agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	1,480,458		1,791,584
Investment securities	11,650		12,770
Available for sale securities	7,740,461		5,804,708
Fair value option securities	1,263,862		283,235
Estimate of Fair Value, Fair Value Disclosure [Member] | Municipal and other tax-exempt securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	44,105		34,507
Investment securities	107,647		138,562
Available for sale securities	1,848		2,864
Estimate of Fair Value, Fair Value Disclosure [Member] | Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	36,928		42,656
Estimate of Fair Value, Fair Value Disclosure [Member] | Other trading securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	50,387		24,411
Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. Treasury [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	2,296		493
Fair value option securities	552,536
Estimate of Fair Value, Fair Value Disclosure [Member] | Residential non-agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	44,803		59,736
Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	3,234,671		2,953,889
Estimate of Fair Value, Fair Value Disclosure [Member] | Other debt securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	204,724		215,966
Available for sale securities	472		35,430
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	761,130		741,749
Interest-bearing cash and cash equivalents	465,458		401,675
Trading securities	0		0
Investment securities	0		0
Available for sale securities	2,296		493
Fair value option securities	552,536
Residential mortgage loans held for sale	0		0
Loans	0		0
Allowance for loan losses	0		0
Loans, net of allowance	0		0
Mortgage servicing rights	0		0
Derviative contracts, net of cash collateral, Assets, Fair value	40,491		44,074
Deposits with no stated maturity	0		0
Time deposits	0		0
Other borrowed funds	0		0
Subordinated debentures	0		0
Derivative contracts, net of cash collateral, Liabilities, Fair Value	0		0
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	0		0
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial real estate [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	0		0
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential mortgage [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	0		0
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Personal [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	0		0
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. government agency debentures [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Investment securities	0		0
Available for sale securities	0		0
Fair value option securities	0		0
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Municipal and other tax-exempt securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Investment securities	0		0
Available for sale securities	0		0
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Other trading securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. Treasury [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	2,296		493
Fair value option securities	552,536
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential non-agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	0		0
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	0		0
Fair Value, Inputs, Level 1 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Other debt securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	0		0
Available for sale securities	0		0
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	0		0
Interest-bearing cash and cash equivalents	0		0
Trading securities	1,675,212		1,956,923
Investment securities	126,999		159,237
Available for sale securities	11,021,783		8,856,155
Fair value option securities	1,263,862
Residential mortgage loans held for sale	268,919		134,014
Loans	0		0
Allowance for loan losses	0		0
Loans, net of allowance	0		0
Mortgage servicing rights	0		0
Derviative contracts, net of cash collateral, Assets, Fair value	311,528		276,855
Deposits with no stated maturity	0		0
Time deposits	0		0
Other borrowed funds	0		0
Subordinated debentures	276,393		261,977
Derivative contracts, net of cash collateral, Liabilities, Fair Value	336,791		362,306
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	0		0
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial real estate [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	0		0
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential mortgage [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	0		0
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Personal [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	0		0
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. government agency debentures [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	63,334		63,765
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	1,480,458		1,791,584
Investment securities	11,650		12,770
Available for sale securities	7,740,461		5,804,708
Fair value option securities	1,263,862		283,235
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Municipal and other tax-exempt securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	44,105		34,507
Investment securities	107,647		138,562
Available for sale securities	1,848		2,864
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	36,928		42,656
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Other trading securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	50,387		24,411
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. Treasury [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	0		0
Fair value option securities	0
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential non-agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	44,803		59,736
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	3,234,671		2,953,889
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Other debt securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	7,702		7,905
Available for sale securities	0		34,958
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and due from banks	0		0
Interest-bearing cash and cash equivalents	0		0
Trading securities	0		0
Investment securities	197,022		208,061
Available for sale securities	472		472
Fair value option securities	0
Residential mortgage loans held for sale	13,568		15,207
Loans	22,265,792		21,478,228
Allowance for loan losses	0		0
Loans, net of allowance	22,265,792		21,478,228
Mortgage servicing rights	193,661		259,254
Derviative contracts, net of cash collateral, Assets, Fair value	0		0
Deposits with no stated maturity	23,923,535		23,150,383
Time deposits	2,241,778		2,073,538
Other borrowed funds	10,193,602		7,071,953
Subordinated debentures	0		0
Derivative contracts, net of cash collateral, Liabilities, Fair Value	0		0
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	14,397,846		13,526,162
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial real estate [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	4,626,804		4,713,747
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential mortgage [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	2,132,158		2,213,951
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Personal [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loans	1,108,984		1,024,368
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. government agency debentures [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Investment securities	0		0
Available for sale securities	0		0
Fair value option securities	0		0
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Municipal and other tax-exempt securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Investment securities	0		0
Available for sale securities	0		0
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Asset-backed securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Other trading securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Trading securities	0		0
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. Treasury [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	0		0
Fair value option securities	0
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Residential non-agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	0		0
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Commercial agency mortgage-backed securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale securities	0		0
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value, Fair Value Disclosure [Member] | Other debt securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	197,022		208,061
Available for sale securities	$ 472		$ 472