Investment securities available for sale (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Par value	$ 38,424	$ 38,101
Amortized Cost	40,297	40,518
Gross Unrealized Gains	5	4
Gross Unrealized Losses	(882)	(980)
Estimated Fair Value	$ 39,420	$ 39,542
Average yield (in hundredths)	1.54%	1.85%
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Securities in a Loss Position for Less Than 12 Months, Fair Value	$ 20,401	$ 0
Securities in a Loss Position for Less Than 12 Months, Unrealized Losses	(585)	0
Securities in a Loss Position for More Than 12 Months, Fair Value	16,675	39,207
Securities in a Loss Position for More Than 12 Months, Unrealized Losses	(297)	(980)
Total Fair Value	37,076	39,207
Total Unrealized Losses	(882)	$ (980)
US Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Average yield (in hundredths)		1.71%
U.S. Government Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Par value	33,918	$ 32,500
Amortized Cost	35,542	34,219
Gross Unrealized Gains	3	0
Gross Unrealized Losses	(774)	(872)
Estimated Fair Value	$ 34,771	33,347
Average yield (in hundredths)	1.49%
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Securities in a Loss Position for Less Than 12 Months, Fair Value	$ 16,609	0
Securities in a Loss Position for Less Than 12 Months, Unrealized Losses	(515)	0
Securities in a Loss Position for More Than 12 Months, Fair Value	16,176	33,347
Securities in a Loss Position for More Than 12 Months, Unrealized Losses	(259)	(872)
Total Fair Value	32,785	33,347
Total Unrealized Losses	(774)	(872)
U.S. Government Agencies [Member] | One To five Years [Member]
Schedule of Available-for-sale Securities [Line Items]
Par value	10,000	10,000
Amortized Cost	10,193	10,324
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(110)	(225)
Estimated Fair Value	$ 10,083	$ 10,099
Average yield (in hundredths)	1.09%	1.10%
U.S. Government Agencies [Member] | Five To Ten Years [Member]
Schedule of Available-for-sale Securities [Line Items]
Par value	$ 20,500	$ 22,500
Amortized Cost	21,923	23,895
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(659)	(647)
Estimated Fair Value	$ 21,264	$ 23,248
Average yield (in hundredths)	2.09%	1.98%
U.S. Government Agencies [Member] | More Than Ten Years [Member]
Schedule of Available-for-sale Securities [Line Items]
Par value	$ 3,418
Amortized Cost	3,426
Gross Unrealized Gains	3
Gross Unrealized Losses	(5)
Estimated Fair Value	$ 3,424
Average yield (in hundredths)	0.82%
Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Par value	$ 3,376
Amortized Cost	3,495
Gross Unrealized Gains	2
Gross Unrealized Losses	(48)
Estimated Fair Value	$ 3,449
Average yield (in hundredths)	1.29%
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Securities in a Loss Position for Less Than 12 Months, Fair Value	$ 3,091	$ 0
Securities in a Loss Position for Less Than 12 Months, Unrealized Losses	(48)	0
Securities in a Loss Position for More Than 12 Months, Fair Value	0	363
Securities in a Loss Position for More Than 12 Months, Unrealized Losses	0	(2)
Total Fair Value	3,091	363
Total Unrealized Losses	(48)	(2)
Mortgage Backed Securities [Member] | One To five Years [Member]
Schedule of Available-for-sale Securities [Line Items]
Par value	2,013
Amortized Cost	2,069
Gross Unrealized Gains	0
Gross Unrealized Losses	(33)
Estimated Fair Value	$ 2,036
Average yield (in hundredths)	1.22%
Mortgage Backed Securities [Member] | More Than Ten Years [Member]
Schedule of Available-for-sale Securities [Line Items]
Par value	$ 1,363	471
Amortized Cost	1,426	484
Gross Unrealized Gains	2	2
Gross Unrealized Losses	(15)	(2)
Estimated Fair Value	$ 1,413	$ 484
Average yield (in hundredths)	1.30%	0.31%
Municipals [Member]
Schedule of Available-for-sale Securities [Line Items]
Par value		$ 5,130
Amortized Cost		5,815
Gross Unrealized Gains		2
Gross Unrealized Losses		(106)
Estimated Fair Value		$ 5,711
Average yield (in hundredths)		2.82%
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Securities in a Loss Position for Less Than 12 Months, Fair Value	$ 701	$ 0
Securities in a Loss Position for Less Than 12 Months, Unrealized Losses	(22)	0
Securities in a Loss Position for More Than 12 Months, Fair Value	499	5,497
Securities in a Loss Position for More Than 12 Months, Unrealized Losses	(38)	(106)
Total Fair Value	1,200	5,497
Total Unrealized Losses	(60)	(106)
Municipals [Member] | Five To Ten Years [Member]
Schedule of Available-for-sale Securities [Line Items]
Par value		1,000
Amortized Cost		1,131
Gross Unrealized Gains		0
Gross Unrealized Losses		(20)
Estimated Fair Value		$ 1,111
Average yield (in hundredths)		2.50%
Municipals [Member] | More Than Ten Years [Member]
Schedule of Available-for-sale Securities [Line Items]
Par value	1,130	$ 4,130
Amortized Cost	1,260	4,684
Gross Unrealized Gains	0	2
Gross Unrealized Losses	(60)	(86)
Estimated Fair Value	$ 1,200	$ 4,600
Average yield (in hundredths)	3.72%	2.89%