Common stock (Tables)

12 Months Ended

Dec. 31, 2014

Schedule of Common Stock Outstanding Roll Forward [Table Text Block]

The following table provides detailed information on the Bank’s common stock activity per class for each of the years in the three-year period ended December 31, 2014:

(Share units)	“Class A”		“Class B”		“Class E”		“Class F”		Total
Authorized		40,000,000		40,000,000		100,000,000		100,000,000		280,000,000

Outstanding at January 1, 2012		6,342,189		2,531,926		28,257,827		-		37,131,942
Conversions		-		-		-		-		-
Restricted stock issued - directors		-		-		32,317		-		32,317
Exercised stock options - compensation plans		-		-		895,674		-		895,674
Restricted stock units - vested		-		-		85,249		-		85,249
Outstanding at December 31, 2012		6,342,189		2,531,926		29,271,067		-		38,145,182
Conversions		-		(11,504)		11,503		-		(1)
Repurchase of common stock		-		-		(1,083)		-		(1,083)
Restricted stock issued - directors		-		-		28,500		-		28,500
Exercised stock options - compensation plans		-		-		276,079		-		276,079
Restricted stock units - vested		-		-		124,490		-		124,490
Outstanding at December 31, 2013		6,342,189		2,520,422		29,710,556		-		38,573,167
Conversions		-		(20,208)		20,208		-		-
Repurchase of common stock		-		(21,164)		(2,110)		-		(23,274)
Restricted stock issued - directors		-		-		28,500		-		28,500
Exercised stock options - compensation plans		-		-		111,427		-		111,427
Restricted stock units - vested		-		-		87,519		-		87,519
Outstanding at December 31, 2014		6,342,189		2,479,050		29,956,100		-		38,777,339

Schedule of Treasury Stock by Class [Table Text Block]

The following table presents information regarding shares repurchased but not retired by the Bank and accordingly classified as treasury stock:

	“Class A”				“Class B”				“Class E”				Total
	Shares		Amount		Shares		Amount		Shares		Amount		Shares		Amount
Outstanding at January 1, 2012		318,140		10,708		568,010		15,655		3,961,748		89,254		4,847,898		115,617
Restricted stock issued - directors		-		-		-		-		(32,317)		(771)		(32,317)		(771)
Exercised stock options - compensation plans		-		-		-		-		(895,674)		(21,361)		(895,674)		(21,361)
Restricted stock units - vested		-				-		-		(85,249)		(2,033)		(85,249)		(2,033)
Outstanding at December 31, 2012		318,140		10,708		568,010		15,655		2,948,508		65,089		3,834,658		91,452
Repurchase of common stock		-		-		-		-		1,083		27		1,083		27
Restricted stock issued - directors		-		-		-		-		(28,500)		(629)		(28,500)		(629)
Exercised stock options - compensation plans		-		-		-		-		(276,079)		(6,094)		(276,079)		(6,094)
Restricted stock units - vested		-		-		-		-		(124,490)		(2,748)		(124,490)		(2,748)
Outstanding at December 31, 2013		318,140		10,708		568,010		15,655		2,520,522		55,645		3,406,672		82,008
Repurchase of common stock		-		-		21,164		587		2,110		53		23,274		640
Restricted stock issued - directors		-		-		-		-		(28,500)		(629)		(28,500)		(629)
Exercised stock options - compensation plans		-		-		-		-		(111,427)		(2,460)		(111,427)		(2,460)
Restricted stock units - vested		-		-		-		-		(87,519)		(1,932)		(87,519)		(1,932)
Outstanding at December 31, 2014		318,140		10,708		589,174		16,242		2,295,186		50,677		3,202,500		77,627