Securities, Securities in Continuous Unrealized Loss Position (Details) $ in Thousands	3 Months Ended		6 Months Ended	9 Months Ended
	Mar. 31, 2018 USD ($) Security	Mar. 31, 2017 USD ($)	Dec. 31, 2017	Mar. 31, 2018 USD ($) Security	Mar. 31, 2017 USD ($)	Jun. 30, 2017 USD ($) Security
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	$ 20,527			$ 20,527		$ 8,412
Less than 12 months, unrealized losses	$ 413			$ 413		$ 92
Less than 12 months, number of securities | Security	27			27		7
More than 12 months, fair value	$ 255			$ 255		$ 0
More than 12 months, unrealized losses	$ 2			$ 2		$ 0
More than 12 months, number of securities | Security	1			1		0
Total, fair value	$ 20,782			$ 20,782		$ 8,412
Total, unrealized losses	$ 415			$ 415		$ 92
Total, number of securities | Security	28			28		7
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	$ 128,538			$ 128,538		$ 42,072
Less than 12 months, unrealized losses	$ 2,600			$ 2,600		$ 346
Less than 12 months, number of securities | Security	214			214		84
More than 12 months, fair value	$ 8,140			$ 8,140		$ 588
More than 12 months, unrealized losses	$ 186			$ 186		$ 20
More than 12 months, number of securities | Security	41			41		7
Total, fair value	$ 136,678			$ 136,678		$ 42,660
Total, unrealized losses	$ 2,786			$ 2,786		$ 366
Total, number of securities | Security	255			255		91
Federal corporate tax rate	21.00%		34.00%
Total Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	$ 149,065			$ 149,065		$ 50,484
Less than 12 months, unrealized losses	$ 3,013			$ 3,013		$ 438
Less than 12 months, number of securities | Security	241			241		91
More than 12 months, fair value	$ 8,395			$ 8,395		$ 588
More than 12 months, unrealized losses	$ 188			$ 188		$ 20
More than 12 months, number of securities | Security	42			42		7
Total, fair value	$ 157,460			$ 157,460		$ 51,072
Total, unrealized losses	$ 3,201			$ 3,201		$ 458
Total, number of securities | Security	283			283		98
Proceeds from sale of available-for-sale securities, debt	$ 0	$ 0		$ 0	$ 0
Gross realized gains (losses) on sale of available-for-sale securities	0	0		0	0
Other-than-temporary impairment losses	0	$ 0		0	$ 0
Maximum [Member]
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Federal corporate tax rate			35.00%
U.S. Government Sponsored Enterprises [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	978			978
Less than 12 months, unrealized losses	$ 20			$ 20
Less than 12 months, number of securities | Security	1			1
More than 12 months, fair value	$ 0			$ 0
More than 12 months, unrealized losses	$ 0			$ 0
More than 12 months, number of securities | Security	0			0
Total, fair value	$ 978			$ 978
Total, unrealized losses	$ 20			$ 20
Total, number of securities | Security	1			1
State and Political Subdivisions [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	$ 5,656			$ 5,656
Less than 12 months, unrealized losses	$ 3			$ 3
Less than 12 months, number of securities | Security	10			10
More than 12 months, fair value	$ 0			$ 0
More than 12 months, unrealized losses	$ 0			$ 0
More than 12 months, number of securities | Security	0			0
Total, fair value	$ 5,656			$ 5,656
Total, unrealized losses	$ 3			$ 3
Total, number of securities | Security	10			10
Mortgage-backed Securities-Residential [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	$ 2,636			$ 2,636		$ 1,164
Less than 12 months, unrealized losses	$ 94			$ 94		$ 27
Less than 12 months, number of securities | Security	4			4		1
More than 12 months, fair value	$ 0			$ 0		$ 0
More than 12 months, unrealized losses	$ 0			$ 0		$ 0
More than 12 months, number of securities | Security	0			0		0
Total, fair value	$ 2,636			$ 2,636		$ 1,164
Total, unrealized losses	$ 94			$ 94		$ 27
Total, number of securities | Security	4			4		1
Mortgage-backed Securities-Multi-family [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	$ 9,790			$ 9,790		$ 6,488
Less than 12 months, unrealized losses	$ 247			$ 247		$ 62
Less than 12 months, number of securities | Security	6			6		4
More than 12 months, fair value	$ 0			$ 0		$ 0
More than 12 months, unrealized losses	$ 0			$ 0		$ 0
More than 12 months, number of securities | Security	0			0		0
Total, fair value	$ 9,790			$ 9,790		$ 6,488
Total, unrealized losses	$ 247			$ 247		$ 62
Total, number of securities | Security	6			6		4
Corporate Debt Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	$ 1,467			$ 1,467		$ 760
Less than 12 months, unrealized losses	$ 49			$ 49		$ 3
Less than 12 months, number of securities | Security	6			6		2
More than 12 months, fair value	$ 255			$ 255		$ 0
More than 12 months, unrealized losses	$ 2			$ 2		$ 0
More than 12 months, number of securities | Security	1			1		0
Total, fair value	$ 1,722			$ 1,722		$ 760
Total, unrealized losses	$ 51			$ 51		$ 3
Total, number of securities | Security	7			7		2
U.S. Government Sponsored Enterprises [Member]
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	$ 7,071			$ 7,071		$ 5,947
Less than 12 months, unrealized losses	$ 171			$ 171		$ 53
Less than 12 months, number of securities | Security	1			1		2
More than 12 months, fair value	$ 1,953			$ 1,953		$ 0
More than 12 months, unrealized losses	$ 47			$ 47		$ 0
More than 12 months, number of securities | Security	1			1		0
Total, fair value	$ 9,024			$ 9,024		$ 5,947
Total, unrealized losses	$ 218			$ 218		$ 53
Total, number of securities | Security	2			2		2
State and Political Subdivisions [Member]
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	$ 34,843			$ 34,843		$ 8,976
Less than 12 months, unrealized losses	$ 491			$ 491		$ 76
Less than 12 months, number of securities | Security	165			165		64
More than 12 months, fair value	$ 3,723			$ 3,723		$ 514
More than 12 months, unrealized losses	$ 85			$ 85		$ 19
More than 12 months, number of securities | Security	37			37		6
Total, fair value	$ 38,566			$ 38,566		$ 9,490
Total, unrealized losses	$ 576			$ 576		$ 95
Total, number of securities | Security	202			202		70
Mortgage-backed Securities-Residential [Member]
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	$ 1,033			$ 1,033		$ 1,864
Less than 12 months, unrealized losses	$ 4			$ 4		$ 2
Less than 12 months, number of securities | Security	1			1		1
More than 12 months, fair value	$ 0			$ 0		$ 0
More than 12 months, unrealized losses	$ 0			$ 0		$ 0
More than 12 months, number of securities | Security	0			0		0
Total, fair value	$ 1,033			$ 1,033		$ 1,864
Total, unrealized losses	$ 4			$ 4		$ 2
Total, number of securities | Security	1			1		1
Mortgage-backed Securities-Multi-family [Member]
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	$ 84,677			$ 84,677		$ 23,823
Less than 12 months, unrealized losses	$ 1,923			$ 1,923		$ 199
Less than 12 months, number of securities | Security	43			43		15
More than 12 months, fair value	$ 2,464			$ 2,464		$ 0
More than 12 months, unrealized losses	$ 54			$ 54		$ 0
More than 12 months, number of securities | Security	3			3		0
Total, fair value	$ 87,141			$ 87,141		$ 23,823
Total, unrealized losses	$ 1,977			$ 1,977		$ 199
Total, number of securities | Security	46			46		15
Corporate Debt Securities [Member]
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value						$ 995
Less than 12 months, unrealized losses						$ 5
Less than 12 months, number of securities | Security						1
More than 12 months, fair value						$ 0
More than 12 months, unrealized losses						$ 0
More than 12 months, number of securities | Security						0
Total, fair value						$ 995
Total, unrealized losses	$ 0			$ 0		$ 5
Total, number of securities | Security						1
Other Securities [Member]
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	914			914		$ 467
Less than 12 months, unrealized losses	$ 11			$ 11		$ 11
Less than 12 months, number of securities | Security	4			4		1
More than 12 months, fair value	$ 0			$ 0		$ 74
More than 12 months, unrealized losses	$ 0			$ 0		$ 1
More than 12 months, number of securities | Security	0			0		1
Total, fair value	$ 914			$ 914		$ 541
Total, unrealized losses	$ 11			$ 11		$ 12
Total, number of securities | Security	4			4		2