Business Combinations - Narrative (Details) - USD ($)					3 Months Ended
	Jan. 01, 2017	Dec. 31, 2016	Nov. 14, 2014	Jul. 31, 2014	Mar. 31, 2018	Jun. 30, 2015	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2013
Business Acquisition [Line Items]
Goodwill							$ 25,638,000	$ 12,673,000	$ 12,673,000
United Financial of North Carolina, Inc.
Business Acquisition [Line Items]
Aggregate transaction consideration		$ 0
Cash paid as deposit premium		$ 0
TriSummit Bancorp
Business Acquisition [Line Items]
Aggregate transaction consideration	$ 36,126,000
Cash paid as deposit premium	$ 16,083,000
Number of shares converted, net of cancellations	86,185
Shares issued for acquisition	765,277
Premises and equipment, net	$ 10,422,000
Cash consideration paid per share (in dollars per share)	$ 25.90
Goodwill	$ 12,540,000
Bank of America
Business Acquisition [Line Items]
Aggregate transaction consideration			$ 9,805,000
Cash paid as deposit premium			$ 9,805,000
Deposit premium paid (as a percent)			2.86%
Average daily deposit period			30 days
Premises and equipment, net			$ 8,993,000
Goodwill			0
Bank of Commerce
Business Acquisition [Line Items]
Aggregate transaction consideration				$ 10,000,000
Cash paid as deposit premium				10,000,000
Premises and equipment, net				$ 135,000
Cash consideration paid per share (in dollars per share)				$ 6.25
Preferred stock redeemed				$ 3,200,000
Assets acquired				122,530,000
Acquired liabilities assumed				114,672,000
Goodwill				1,922,000
Adjustments to goodwill, increase/(decrease)						$ (2,031,000)
As Recorded by the Company | Bank of America
Business Acquisition [Line Items]
Total consideration			9,805,000
Acquired loans, net of allowance			1,045,000
Premises and equipment, net			$ 8,993,000
As Recorded by the Company | Bank of Commerce
Business Acquisition [Line Items]
Total consideration				10,000,000
Goodwill				$ 1,922,000
Scenario, Forecast | United Financial of North Carolina, Inc.
Business Acquisition [Line Items]
Cash paid as deposit premium					$ 225
Common Stock | TriSummit Bancorp
Business Acquisition [Line Items]
Right to receive cash (in dollars per share)	$ 4.40
Number of securities called by each share of TriSummit (in shares)	0.2099
TriSummit Bancorp | TriSummit Bancorp
Business Acquisition [Line Items]
Percentage of outstanding options canceled	50.00%
TriSummit Bancorp | Series B, C, and D TARP Preferred Stock | TriSummit Bancorp
Business Acquisition [Line Items]
Value of redeemed preferred stock	$ 7,222,000