Mid Penn Bancorp (MPB) S-4 17 Aug 17 Registration of securities issued in business combination transactions Financial data

Document and Entity Information

Document and Entity Information	6 Months Ended
	Jun. 30, 2017
Document And Entity Information [Abstract]
Document Type	S4
Amendment Flag	false
Document Period End Date	Jun. 30, 2017
Trading Symbol	MPB
Entity Registrant Name	MID PENN BANCORP INC
Entity Central Index Key	879,635
Entity Filer Category	Smaller Reporting Company

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($)	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
ASSETS
Cash and due from banks	$ 25,246,000	$ 13,493,000	$ 12,329,000
Interest-bearing balances with other financial institutions	2,813,000	2,003,000	955,000
Federal funds sold	1,120,000	30,477,000
Total cash and cash equivalents	29,179,000	45,973,000	13,284,000
Interest-bearing time deposits with other financial institutions			4,317,000
Investment securities available for sale, at fair value	111,353,000	133,625,000	135,721,000
Investment securities held to maturity, at amortized cost	71,096,000	0	0
Loans held for sale	2,369,000	1,959,000	2,678,000
Loans and leases, net of unearned interest	862,307,000	813,924,000	736,513,000
Less: Allowance for loan and lease losses	(7,713,000)	(7,183,000)	(6,168,000)
Net loans and leases	854,594,000	806,741,000	730,345,000
Bank premises and equipment, net	11,190,000	11,074,000	13,993,000
Bank premises and equipment held for sale		1,894,000
Cash surrender value of life insurance	12,911,000	12,780,000	12,516,000
Restricted investment in bank stocks	3,985,000	2,443,000	4,266,000
Foreclosed assets held for sale		224,000	1,185,000
Accrued interest receivable	3,991,000	3,928,000	3,813,000
Deferred income taxes	3,396,000	4,286,000	1,821,000
Goodwill	3,918,000	3,918,000	3,918,000
Core deposit and other intangibles, net	486,000	539,000	665,000
Other assets	3,408,000	3,215,000	3,116,000
Total Assets	1,111,876,000	1,032,599,000	931,638,000
LIABILITIES & SHAREHOLDERS' EQUITY
Deposits: Noninterest-bearing demand	140,837,000	122,811,000	103,721,000
Deposits: Interest-bearing demand	339,057,000	317,533,000	247,356,000
Deposits: Money Market	240,107,000	252,271,000	208,386,000
Deposits: Savings	63,232,000	60,163,000	56,731,000
Deposits: Time	204,235,000	182,595,000	160,849,000
Total Deposits	987,468,000	935,373,000	777,043,000
Short-term borrowings	21,468,000		31,596,000
Long-term debt	13,467,000	13,581,000	40,305,000
Subordinated debt	7,419,000	7,414,000	7,414,000
Accrued interest payable	788,000	515,000	390,000
Other liabilities	5,630,000	5,249,000	4,822,000
Total Liabilities	1,036,240,000	962,132,000	861,570,000
Shareholders' Equity:
Common stock	4,235,000	4,233,000	4,227,000
Additional paid-in capital	40,775,000	40,688,000	40,559,000
Retained earnings	31,637,000	28,399,000	23,470,000
Accumulated other comprehensive loss	(1,011,000)	(2,853,000)	1,812,000
Total Shareholders' Equity	75,636,000	70,467,000	70,068,000
Total Liabilities and Shareholders' Equity	$ 1,111,876,000	$ 1,032,599,000	$ 931,638,000

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Investment securities held-to-maturity, fair value	$ 71,199	$ 0
Common Stock, Par Value	$ 1	$ 1	$ 1
Common Stock, Shares Authorized	10,000,000	10,000,000	10,000,000
Common Stock, Shares, Issued	4,235,237	4,233,297	4,226,717
Common Stock, Shares, Outstanding	4,235,237	4,233,297

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
INTEREST INCOME
Interest and fees on loans and leases	$ 9,949	$ 8,905	$ 19,651	$ 17,712	$ 36,402	$ 32,840	$ 26,905
Interest on interest-bearing balances	5	2	7	9	12	44	41
Interest and dividends on investment securities:
U.S. Treasury and government agencies	574	311	1,019	633	1,346	1,222	1,346
State and political subdivision obligations, tax-exempt	264	548	580	1,012	2,066	2,000	2,180
Other securities	64	78	107	172	304	382	155
Interest on federal funds sold	23	15	74	18	82	2
Total Interest Income	10,879	9,859	21,438	19,556	40,212	36,490	30,627
INTEREST EXPENSE
Interest on deposits	1,277	1,092	2,481	2,131	4,514	3,889	3,852
Interest on short-term borrowings	13	12	13	25	15	47	55
Interest on long-term and subordinated debt	179	222	359	452	838	671	520
Total Interest Expense	1,469	1,326	2,853	2,608	5,367	4,607	4,427
Net Interest Income	9,410	8,533	18,585	16,948	34,845	31,883	26,200
Provision for Loan and Lease Losses	100	395	225	735	1,870	1,065	1,617
Net Interest Income After Provision for Loan and Lease Losses	9,310	8,138	18,360	16,213	32,975	30,818	24,583
NONINTEREST INCOME
Income from fiduciary activities	200	139	396	245	481	466	552
Service charges on deposits	174	158	379	313	684	690	584
Net gain on sales of investment securities	12	213	20	213	1,046	325	168
Earnings from cash surrender value of life insurance	66	65	131	135	264	269	201
Mortgage banking income	225	246	416	432	922	456	313
ATM debit card interchange income	232	209	456	409	844	741	544
Merchant services income	92	85	166	152	317	235	254
Net gain on sales of SBA loans	157	75	441	265	470	252	119
Other income	204	208	393	466	896	679	549
Total Noninterest Income	1,362	1,398	2,798	2,630	5,924	4,113	3,284
NONINTEREST EXPENSE
Salaries and employee benefits	4,159	3,723	8,389	7,446	15,564	14,043	10,879
Occupancy expense, net	593	499	1,241	1,046	2,064	1,947	1,313
Equipment expense	370	411	751	846	1,689	1,477	1,205
Pennsylvania bank shares tax expense	160	206	330	409	648	408	365
FDIC Assessment	194	147	388	300	688	613	542
Legal and professional fees	189	183	366	385	711	588	516
Marketing and advertising expense	131	139	238	223	500	533	308
Software licensing	370	334	699	665	1,380	1,472	965
Telephone expense	133	143	259	285	548	569	467
Loss on sale or write-down of foreclosed assets	6	28	88	132	217	111	204
Intangible amortization	24	34	53	71	126	114	63
Merger and acquisition expense	14		224			762	573
Other expenses	1,215	1,074	2,334	2,095	4,683	4,122	3,304
Total Noninterest Expense	7,558	6,921	15,360	13,903	28,818	26,759	20,704
Income before income tax and equity in undistributed earnings (loss) of subsidiaries	3,114	2,615	5,798	4,940	10,081	8,172	7,163
Provision for Income Taxes	769	593	1,459	1,113	2,277	1,644	1,462
NET INCOME	$ 2,345	$ 2,022	$ 4,339	$ 3,827	$ 7,804	$ 6,528	$ 5,701
PER COMMON SHARE DATA:
Basic and Diluted Earnings Per Common Share	$ 0.55	$ 0.48	$ 1.02	$ 0.91	$ 1.85	$ 1.47	$ 1.53
Cash Dividends Paid	$ 0.13	0.12	$ 0.36	$ 0.34
Cash Dividends Declared		$ 0.12			$ 0.68	$ 0.44	$ 0.45
NET INCOME AVAILABLE TO COMMON SHAREHOLDERS		$ 2,022			$ 7,804	$ 6,038	$ 5,351
Series B Preferred Stock [Member]
NONINTEREST EXPENSE
Preferred stock dividends and redemption premium						473	350
PER COMMON SHARE DATA:
Preferred stock dividends						373	$ 350
Series C Preferred Stock [Member]
PER COMMON SHARE DATA:
Preferred stock dividends						$ 17

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands		3 Months Ended		6 Months Ended		12 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income		$ 2,345	$ 2,022	$ 4,339	$ 3,827	$ 7,804	$ 6,528	$ 5,701
Other comprehensive (loss) income:
Unrealized gains arising during the period on available-for-sale securities, net of income taxes, respectively		1,480	1,854	1,859	2,220	(3,794)	154	2,482
Reclassification adjustment for net gain on sales of available-for-sale securities included in net income, net of income taxes, respectively	[1]	(8)	(140)	(13)	(140)	(690)	(215)	(111)
Change in defined benefit plans, net of income taxes, respectively	[2]	(1)	(2)	(4)	(116)	(181)	360	14
Total other comprehensive (loss) income		1,471	1,712	1,842	1,964	(4,665)	299	2,385
Total comprehensive income		$ 3,816	$ 3,734	$ 6,181	$ 5,791	$ 3,139	$ 6,827	$ 8,086
[1]	Amounts are included in net gain on sales of investment securities on the Consolidated Statements of Income as a separate element within total noninterest income.
[2]	Amounts are included in the computation of net periodic benefit cost and are included in salaries and employee benefits on the Consolidated Statements of Income as a separate element within total noninterest expense.

Consolidated Statements of Com6

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Unrealized (losses) gains arising during the period on available for sale securities, tax	$ 763	$ 955	$ 958	$ 1,144	$ (1,954)	$ 80	$ 1,280
Reclassification adjustment for net gain on sales of available for sale securities included in net income, tax	(4)	(73)	(7)	(73)	(356)	(110)	(57)
Change in defined benefit plans, tax	$ (1)	$ (1)	$ (2)	$ (60)	$ (93)	$ 185	$ 7

Consolidated Statements of Chan

Consolidated Statements of Changes In Shareholders' Equity - USD ($) $ in Thousands	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Series B Preferred Stock [Member]	Series B Preferred Stock [Member]Preferred Stock [Member]	Series B Preferred Stock [Member]Retained Earnings [Member]	Series C Preferred Stock [Member]	Series C Preferred Stock [Member]Preferred Stock [Member]	Series C Preferred Stock [Member]Retained Earnings [Member]
Balance at Dec. 31, 2013	$ 52,916	$ 5,000	$ 3,494	$ 29,853	$ 15,441	$ (872)
Net income	5,701				5,701
Total other comprehensive (loss) income, net of taxes	2,385					2,385
Employee Stock Purchase Plan	53		4	49
Common stock dividends	(1,575)				(1,575)
Preferred stock dividends							$ (350)		$ (350)
Balance at Dec. 31, 2014	59,130	5,000	3,498	29,902	19,217	1,513
Series C preferred stock in connection with Phoenix acquisition										$ 1,750	$ 1,750
Net income	6,528				6,528
Total other comprehensive (loss) income, net of taxes	299					299
Employee Stock Purchase Plan	66		4	62
Common stock dividends	(1,785)				(1,785)
Preferred stock dividends							(373)		(373)	(17)		$ (17)
Preferred stock redemption							(5,000)	$ (5,000)		$ (1,750)	$ (1,750)
Preferred stock redemption premium							$ (100)		$ (100)
Common stock issued to Phoenix shareholders	11,292		724	10,568
Restricted stock activity	28		1	27
Balance at Dec. 31, 2015	70,068		4,227	40,559	23,470	1,812
Net income	3,827				3,827
Total other comprehensive (loss) income, net of taxes	1,964					1,964
Employee Stock Purchase Plan	35		2	33
Common stock dividends	(1,437)				(1,437)
Restricted stock activity	17			17
Balance at Jun. 30, 2016	74,474		4,229	40,609	25,860	3,776
Balance at Dec. 31, 2015	70,068		4,227	40,559	23,470	1,812
Net income	7,804				7,804
Total other comprehensive (loss) income, net of taxes	(4,665)					(4,665)
Employee Stock Purchase Plan	82		4	78
Common stock dividends	(2,875)				(2,875)
Restricted stock activity	53		2	51
Balance at Dec. 31, 2016	70,467	$ 0	4,233	40,688	28,399	(2,853)
Net income	4,339				4,339
Total other comprehensive (loss) income, net of taxes	1,842					1,842
Employee Stock Purchase Plan	52		2	50
Common stock dividends	(1,101)				(1,101)
Restricted stock activity	37			37
Balance at Jun. 30, 2017	$ 75,636		$ 4,235	$ 40,775	$ 31,637	$ (1,011)

Consolidated Statements of Cha8

Consolidated Statements of Changes In Shareholders' Equity (Parenthetical) - shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Statement of Stockholders' Equity [Abstract]
Stock issued during period, shares, Employee Stock Purchase Plans	4,465	4,162
Stock issued during period, shares, acquisitions		723,851
Stock issued during period, shares, Restricted stock activity	2,115	875

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Activities:
Net income	$ 4,339,000	$ 3,827,000	$ 7,804,000	$ 6,528,000	$ 5,701,000
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for Loan and Lease Losses	225,000	735,000	1,870,000	1,065,000	1,617,000
Depreciation	715,000	820,000	1,658,000	1,485,000	1,235,000
Amortization of intangibles	53,000	71,000	126,000	100,000	62,000
Net (accretion) amortization of security discounts/premiums	(742,000)	11,330,000	11,709,000	4,251,000	1,250,000
Gain on sales of investment securities	(20,000)	(213,000)	(1,046,000)	(325,000)	(168,000)
Earnings on cash surrender value of life insurance	(131,000)	(135,000)	(264,000)	(269,000)	(201,000)
Mortgage loans originated for sale	(23,234,000)	(7,731,000)	(42,888,000)	(26,083,000)	(16,775,000)
Proceeds from sales of mortgage loans originated for sale	23,240,000	8,163,000	43,810,000	26,539,000	17,088,000
Gain on sale of mortgage loans	(416,000)	(432,000)	(922,000)	(456,000)	(313,000)
SBA loans originated for sale	(5,605,000)	(3,318,000)	(5,872,000)	(3,484,000)	(1,168,000)
Proceeds from sales of SBA loans originated for sale	6,046,000	3,583,000	6,342,000	3,736,000	1,287,000
Gain on sale of SBA loans	(441,000)	(265,000)	(470,000)	(252,000)	(119,000)
Loss on disposal of property, plant, and equipment	26,000		142,000		18,000
Loss on sale or write-down of foreclosed assets	88,000	132,000	217,000	111,000	204,000
Restricted stock compensation expense	37,000	17,000	53,000	27,000
Deferred income tax (benefit) expense	(65,000)	16,000	(336,000)	997,000	(112,000)
Increase in accrued interest receivable	(63,000)	(130,000)	(115,000)	(367,000)	(354,000)
(Increase) decrease in other assets	(193,000)	161,000	(99,000)	333,000	(547,000)
Increase in accrued interest payable	273,000	308,000	125,000	9,000	(44,000)
Increase in other liabilities	381,000	1,847,000	427,000	(771,000)	9,000
Net cash provided by operating activities	4,513,000	18,786,000	22,271,000	13,174,000	8,670,000
Investing Activities:
Net decrease in interest-bearing time deposits with other financial institutions		3,330,000	4,317,000	1,455,000	1,741,000
Proceeds from the sale of available-for-sale securities	37,667,000	38,501,000	111,390,000	37,142,000	13,729,000
Proceeds from the maturity or call of available-for-sale securities	3,579,000	6,264,000	16,110,000	11,940,000	13,585,000
Purchases of available-for-sale securities	(13,827,000)	(84,352,000)	(142,861,000)	(35,858,000)	(43,633,000)
Purchases of held-to-maturity securities	(72,684,000)
Net cash received from acquisition				8,095,000
(Purchases) redemptions of restricted investment in bank stock	(1,542,000)	1,623,000	1,823,000	(576,000)	(212,000)
Net increase in loans and leases	(48,078,000)	(30,054,000)	(77,795,000)	(60,043,000)	(27,170,000)
Proceeds from the sale of bank premises and equipment held for sale	2,201,000
Purchases of bank premises and equipment	(1,164,000)	(319,000)	(775,000)	(1,461,000)	(1,009,000)
Proceeds from the sale of foreclosed assets	136,000	614,000	992,000	403,000	1,077,000
Net Cash Used In Investing Activities	(93,712,000)	(64,393,000)	(86,799,000)	(38,903,000)	(41,892,000)
Financing Activities:
Net increase in deposits	52,095,000	116,397,000	158,330,000	15,883,000	29,792,000
Net increase (decrease) in short-term borrowings	21,468,000	(31,596,000)	(31,596,000)	31,018,000	(23,255,000)
Common stock dividend paid	(1,101,000)	(1,437,000)	(2,875,000)	(1,785,000)	(1,575,000)
Employee Stock Purchase Plan	52,000	35,000	82,000	66,000	53,000
Long-term debt repayment	(109,000)	(10,116,000)	(26,724,000)	(16,226,000)	(184,000)
Net Cash Provided By Financing Activities	72,405,000	73,283,000	97,217,000	29,131,000	34,481,000
Proceeds from long-term debt borrowings					30,000,000
Deferred financing fees paid for subordinated debt issuance				(85,000)
Subordinated debt issuance				7,500,000
Net (decrease) increase in cash and cash equivalents	(16,794,000)	27,676,000	32,689,000	3,402,000	1,259,000
Cash and cash equivalents, beginning of period	45,973,000	13,284,000	13,284,000	9,882,000	8,623,000
Cash and cash equivalents, end of period	29,179,000	40,960,000	45,973,000	13,284,000	9,882,000
Supplemental Disclosures of Cash Flow Information:
Interest paid	2,580,000	2,300,000	5,242,000	4,566,000	4,471,000
Income taxes paid	$ 2,190,000	565,000	1,700,000	1,130,000	1,520,000
Supplemental Noncash Disclosures:
Loan transfers to foreclosed assets held for sale		$ 101,000	248,000	1,135,000	881,000
Asset transfers to bank premises and equipment held for sale			$ 1,894,000
Phoenix Bancorp Inc. [Member]
Supplemental Noncash Disclosures:
Common stock issued to Phoenix shareholders				11,292,000
Assets Acquired:
Securities				11,331,000
Loans				110,363,000
Restricted stock				509,000
Property and equipment				1,792,000
Deferred income taxes				503,000
Accrued interest receivable				388,000
Core deposit and other intangible assets				578,000
Bank-owned life insurance				3,673,000
Other assets				624,000
Assets acquired				129,761,000
Liabilities Assumed:
Deposits				123,238,000
Accrued interest payable				32,000
Long-term debt				3,570,000
Other liabilities				876,000
Liabilities assumed				127,716,000
Equity Acquired:
Preferred stock				1,750,000
Series B Preferred Stock [Member]
Financing Activities:
Preferred stock dividends and redemption premium paid				(473,000)	$ (350,000)
Preferred stock redemption				(5,000,000)
Series C Preferred Stock [Member]
Financing Activities:
Preferred stock dividends paid				(17,000)
Preferred stock redemption				$ (1,750,000)

Basis of Presentation

Basis of Presentation	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	(1) Basis of Presentation The accompanying consolidated financial statements include the accounts of Mid Penn Bancorp, Inc. (the “Company”) and its wholly-owned subsidiaries, Mid Penn Bank (the “Bank”), and the Bank’s former wholly-owned subsidiary, Mid Penn Insurance Services, LLC (collectively, “Mid Penn”). All material intercompany accounts and transactions have been eliminated in consolidation. Effective March 1, 2016, Mid Penn Insurance Services, LLC, an immaterial subsidiary of the Bank, was liquidated. Certain information and disclosures normally included in consolidated financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Mid Penn believes the information presented is not misleading and the disclosures are adequate. For comparative purposes, the June 30, 2016 and December 31, 2016 balances have been reclassified, when, and if necessary, to conform to the 2017 presentation. Such reclassifications had no impact on net income. The results of operations for interim periods are not necessarily indicative of operating results expected for the full year. These interim consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K On March 29, 2017, Mid Penn announced the signing of a definitive merger agreement with The Scottdale Bank and Trust Company (“Scottdale”). Under the merger agreement, Scottdale will merge with and into Mid Penn Bank, with Mid Penn Bank as the surviving bank. Before the merger is completed, the shareholders of Mid Penn and Scottdale must approve and adopt the merger agreement, and customary regulatory approvals must be received. Refer to Note 12, Agreement and Plan of Merger Form 8-K Mid Penn has evaluated events and transactions occurring subsequent to the balance sheet date of June 30, 2017, for items that should potentially be recognized or disclosed in these consolidated financial statements. The evaluation was conducted through the date these consolidated financial statements were issued.	(1) Basis of Presentation The accompanying consolidated financial statements include the accounts of Mid Penn Bancorp, Inc. and its wholly-owned subsidiary Mid Penn Bank (the “Bank”), and the Bank’s former wholly-owned subsidiary Mid Penn Insurance Services, LLC, which was closed, effective March 1, 2016 (collectively, “Mid Penn”). All material intercompany accounts and transactions have been eliminated in consolidation. Each of Mid Penn’s lines of business are part of the same reporting segment, community banking, whose operating results are regularly reviewed and managed by a centralized executive management group. As a result, Mid Penn has only one reportable segment for financial reporting purposes. The comparability of the results of operations for the year ended 2016 compared to 2015 and 2014, in general, have been impacted by the acquisition of Phoenix as further described in Note 4. For comparative purposes, the 2015 and 2014 balances have been reclassified to conform to the 2016 presentation. Such reclassifications had no impact on net income.

Nature of Business

Nature of Business	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business	(2) Nature of Business The Bank engages in a full-service commercial banking and trust business, making available to the community a wide range of financial services, including, but not limited to, mortgage and home equity loans, secured and unsecured commercial and consumer loans, lines of credit, construction financing, farm loans, community development loans, loans to non-profit entities and local government loans and various types of time and demand deposits, including but not limited to, checking accounts, savings accounts, clubs, money market deposit accounts, certificates of deposit, and IRAs. In addition, the Bank provides a full range of trust services through its Trust Department. Deposits are insured by the Federal Deposit Insurance Corporation (“FDIC”) to the extent provided by law. The financial services are provided to individuals, partnerships, non-profit organizations, and corporations through its 21 retail banking offices located in Cumberland, Dauphin, Lancaster, Luzerne, Northumberland, and Schuylkill Counties. A decision was made to close Mid Penn Insurance Services, LLC, effective March 1, 2016 due to a lack of activity within the subsidiary. Mid Penn Insurance Services, LLC was an immaterial subsidiary of the Bank, and was immaterial to Mid Penn’s consolidated results.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	(3) Summary of Significant Accounting Policies The accounting and reporting policies of Mid Penn conform with accounting principles generally accepted in the United States of America (“GAAP”) and to general practice within the financial industry. The following is a description of the more significant accounting policies. (a) Use of Estimates The preparation of financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates. Material estimates that are particularly susceptible to significant change relate to the determination of the allowance for loan and lease losses, the assessment of other-than-temporary impairment of investment securities, the valuation of the goodwill for impairment, and the valuation of assets acquired and liabilities assumed in business combinations. (b) Cash and Cash Equivalents For purposes of the consolidated statements of cash flows, cash and cash equivalents include cash on hand, balances due from banks, and federal funds sold, all of which mature within ninety days. (c) Interest-bearing Time Deposits with Other Financial Institutions Interest-bearing time deposits with other financial institutions consist of certificates of deposits in other financial institutions with maturities within one year. (d) Investment Securities Available-for-sale securities include debt and equity securities. Debt and equity securities are reported at fair value, with unrealized holding gains and losses excluded from earnings and reported, net of deferred income taxes, as a component of accumulated other comprehensive income (loss) within shareholders’ equity. Premiums and discounts on debt securities are amortized as an adjustment to interest income using the interest method. Realized gains and losses on sales of investment securities are computed on the basis of specific identification of the cost of each security. Net gains on sales of investment securities were $1,046,000 in 2016, $325,000 in 2015, and $168,000 in 2014. Mid Penn had no held-to-maturity securities in 2016 and 2015. (e) Loans Held for Sale Mortgage loans originated and intended for sale in the secondary market are included in loans held for sale and are carried at fair value, as determined by outstanding commitments from investors. Gains and losses on sales of mortgage loans are included in the Consolidated Statements of Income in mortgage banking income. Mortgage banking income was $922,000 in 2016, $456,000 in 2015, and $313,000 in 2014. (f) Loans and Allowance for Loan and Lease Losses Loans receivable that management has the intent and ability to hold for the foreseeable future or until maturity or payoff are stated at their outstanding unpaid principal balances, net of an allowance for loan losses and any deferred fees or costs. Interest income is accrued on the unpaid principal balance. Residential loans held for sale are carried at fair value and are included in loans held for sale on the balance sheet. Loan origination fees, net of certain direct origination costs, are deferred and recognized as an adjustment of the yield (interest income) of the related loans. These amounts are generally being amortized over the contractual life of the loan. Premiums and discounts on purchased loans are amortized as adjustments to interest income using the effective yield method. The loan portfolio is segmented into commercial and consumer loans. Commercial loans consist of the following classes: commercial and industrial, commercial real estate, commercial real estate-construction and lease financing. Consumer loans consist of the following classes: residential mortgage loans, home equity loans and other consumer loans. For all classes of loans, the accrual of interest is discontinued when the contractual payment of principal or interest has become 90 days or more past due or management has serious doubts about further collectability of principal or interest, even though the loan is currently performing. A loan may remain on accrual status if it is in the process of collection and is either guaranteed or well secured. When a loan is placed on nonaccrual status, unpaid interest is credited to income. Interest received on nonaccrual loans, including impaired loans, generally is either applied against principal or reported as interest income, according to management’s judgment as to the collectability of principal. Generally, loans are restored to accrual status when the obligation is brought current, has performed in accordance with the contractual terms for a reasonable period of time (generally six months) and the ultimate collectability of the total contractual principal and interest is no longer in doubt. The past due status of all classes of loans receivable is determined based on contractual due dates for loan payments. Commercial and industrial Mid Penn originates commercial and industrial loans. Most of the Bank’s commercial and industrial loans have been extended to finance local and regional businesses and include short-term loans to finance machinery and equipment purchases, inventory, and accounts receivable. Commercial loans also involve the extension of revolving credit for a combination of equipment acquisitions and working capital in expanding companies. The maximum term for loans extended on machinery and equipment is based on the projected useful life of such machinery and equipment. Generally, the maximum term on non-mortgage lines of credit is one year. The loan-to-value ratio on such loans and lines of credit generally may not exceed 80% of the value of the collateral securing the loan. The Bank’s commercial business lending policy includes credit file documentation and analysis of the borrower’s character, capacity to repay the loan, the adequacy of the borrower’s capital and collateral as well as an evaluation of conditions affecting the borrower. Analysis of the borrower’s past, present, and future cash flows is also an important aspect of the Bank’s current credit analysis. Nonetheless, such loans are believed to carry higher credit risk than other extensions of credit. Commercial and industrial loans typically are made on the basis of the borrower’s ability to make repayment from the cash flow of the borrower’s business. As a result, the availability of funds for the repayment of commercial business loans may be substantially dependent on the success of the business itself, which, in turn, is likely to be dependent upon the general economic environment. Mid Penn’s commercial and industrial loans are usually, but not always, secured by business assets and personal guarantees. However, the collateral securing the loans may depreciate over time, may be difficult to appraise, and may fluctuate in value based on the success of the business. Commercial real estate and commercial real estate—construction Commercial real estate and commercial real estate construction loans generally present a higher level of risk than loans secured by one to four family residences. This greater risk is due to several factors, including the concentration of principal in a limited number of loans and borrowers, the effect of general economic conditions on income producing properties, and the increased difficulty of evaluating and monitoring these types of loans. In addition, the repayment of loans secured by commercial real estate is typically dependent upon the successful operation of the related real estate project. If the cash flow from the project is reduced, the borrower’s ability to repay the loan may be impaired. Residential mortgage Mid Penn offers a wide array of residential mortgage loans for both permanent structures and those under construction. The Bank’s residential mortgage originations are secured primarily by properties located in its primary market and surrounding areas. Residential mortgage loans have terms up to a maximum of 30 years and with loan to value ratios up to 100% of the lesser of the appraised value of the security property or the contract price. Private mortgage insurance is generally required in an amount sufficient to reduce the Bank’s exposure to at or below the 85% loan to value level. Residential mortgage loans generally do not include prepayment penalties. In underwriting residential mortgage loans, the Bank evaluates both the borrower’s ability to make monthly payments and the value of the property securing the loan. Most properties securing real estate loans made by Mid Penn are appraised by independent fee appraisers. The Bank generally requires borrowers to obtain title insurance and fire and property insurance (including flood insurance, if necessary) in an amount not less than the amount of the loan. Real estate loans originated by the Bank generally contain a “due on sale” clause allowing the Bank to declare the unpaid principal balance due and payable upon the sale of the security property. The Bank underwrites residential mortgage loans to the standards established by the secondary mortgage market, i.e., Fannie Mae, Ginnie Mae, Freddie Mac, or Pennsylvania Housing Finance Agency standards, with the intention of selling the majority of residential mortgages originated into the secondary market. In the event that the facts and circumstances surrounding a residential mortgage application do not meet all underwriting conditions of the secondary mortgage market, the Bank will evaluate the failed conditions and evaluate the potential risk of holding the residential mortgage in the Bank’s portfolio rather than rejecting the loan request. In the event that the loan is held in the Bank’s portfolio, the interest rate on the residential mortgage typically would be increased to compensate for the added portfolio risk. Consumer, including home equity Mid Penn offers a variety of secured consumer loans, including home equity, automobile, and deposit secured loans. In addition, the Bank offers other secured and unsecured consumer loans. Most consumer loans are originated in Mid Penn’s primary market and surrounding areas. The largest component of Mid Penn’s consumer loan portfolio consists of fixed rate home equity loans and variable rate home equity lines of credit. Substantially all home equity loans and lines of credit are secured by second mortgages on principal residences. The Bank will lend amounts, which, together with all prior liens, typically may be up to 85% of the appraised value of the property securing the loan. Home equity term loans may have maximum terms up to 20 years while home equity lines of credit generally have maximum terms of five years. Consumer loan terms vary according to the type and value of collateral, length of contract and creditworthiness of the borrower. The underwriting standards employed by the Bank for consumer loans include an application, a determination of the applicant’s payment history on other debts, and an assessment of ability to meet existing obligations and payments on the proposed loan. Although creditworthiness of the applicant is a primary consideration, the underwriting process also includes a comparison of the value of the collateral, if any, in relation to the proposed loan amount. Consumer loans may entail greater credit risk than do residential mortgage loans, particularly in the case of consumer loans which are unsecured or are secured by rapidly depreciable assets, such as automobiles or recreational equipment. In such cases, any repossessed collateral for a defaulted consumer loan may not provide an adequate source of repayment of the outstanding loan balance. In addition, consumer loan collections are dependent on the borrower’s continuing financial stability, and thus are more likely to be affected by adverse personal circumstances. Furthermore, the application of various federal and state laws, including bankruptcy and insolvency laws, may limit the amount that can be recovered on such loans. Junior liens inherently have more credit risk by virtue of the fact that another financial institution may have a higher security position in the case of foreclosure liquidation of collateral to extinguish the debt. Generally, foreclosure actions could become more prevalent if the real estate market weakens and property values deteriorate. Allowance for Loan and Lease Losses The allowance for credit losses consists of the allowance for loan and lease losses and the reserve for unfunded lending commitments. The allowance for loan and lease losses represents management’s estimate of losses inherent in the loan portfolio as of the balance sheet date and is recorded as a reduction to loans. The reserve for unfunded lending commitments represents management’s estimate of losses inherent in its unfunded loan commitments and is recorded in other liabilities on the consolidated balance sheet and was $120,000 at December 31, 2016 and $94,500 at December 31, 2015. The allowance for loan and lease losses is increased by the provision for loan and lease losses, and decreased by charge-offs, net of recoveries. Loans deemed to be uncollectible are charged against the allowance for loan and lease losses, and subsequent recoveries, if any, are credited to the allowance. All, or part, of the principal balance of loans are charged off to the allowance as soon as it is determined that the repayment of all, or part, of the principal balance is highly unlikely. Non-residential consumer loans are generally charged off no later than 120 days past due on a contractual basis, earlier in the event of bankruptcy, or if there is an amount deemed uncollectible. Because all identified losses are immediately charged off, no portion of the allowance for loan and lease losses is restricted to any individual loan or groups of loans, and the entire allowance is available to absorb any and all loan losses. The allowance for credit losses is maintained at a level considered adequate to provide for losses that can be reasonably anticipated. Management performs a monthly evaluation of the adequacy of the allowance. The allowance is based on Mid Penn’s past loan loss experience, known and inherent risks in the portfolio, adverse situations that may affect the borrower’s ability to repay, the estimated value of any underlying collateral, composition of the loan portfolio, current economic conditions, and other relevant factors. This evaluation is inherently subjective as it requires material estimates that may be susceptible to significant revision as more information becomes available. The allowance consists of specific, general and unallocated components. The specific component relates to loans that are classified as impaired. For loans that are classified as impaired, an allowance is established when the DCF, collateral value, or observable market price of the impaired loan is lower than the carrying value of that loan. The general component covers pools of loans by loan class including commercial loans not considered impaired, as well as smaller balance homogeneous loans, such as residential real estate, home equity and other consumer loans. These pools of loans are evaluated for loss exposure based upon historical loss rates for each of these categories of loans, adjusted for qualitative factors. These qualitative risk factors include changes in economic conditions, fluctuations in loan quality measures, changes in collateral values, changes in the experience of the lending staff and loan review systems, changes in lending policies and procedures, including underwriting standards, changes in the mix and volume of loans originated, the effect of other external factors such as competition and legal and regulatory requirements on the level of estimated credit losses in the existing loan portfolio, and shifting industry or portfolio concentrations. Each factor is assigned a value to reflect improving, stable or declining conditions based on management’s best judgment using relevant information available at the time of the evaluation. Adjustments to the factors are supported through documentation of changes in conditions in a narrative accompanying the allowance for loan loss calculation. Mid Penn generally considers a commercial loan (consisting of commercial and industrial, commercial real estate, commercial real estate-construction, and lease financing loan classes) to be impaired when it becomes 90 days or more past due and not in the process of collection or sooner when it is probable that Mid Penn will be unable to collect all contractual principal and interest due. This methodology assumes the borrower cannot or will not continue to make additional payments. At that time the loan would generally be considered collateral dependent as the DCF method would generally indicate no operating income available for evaluating the collateral position; therefore, most impaired loans are deemed to be collateral dependent. In addition, Mid Penn’s rating system assumes any loans classified as nonaccrual, included in the substandard rating, to be impaired, and most of these loans are considered collateral dependent; therefore, most of Mid Penn’s impaired loans, whether reporting a specific allocation or not, are considered collateral dependent. Mid Penn evaluates loans for charge-off on a monthly basis. Policies that govern the recommendation for charge-off are unique to the type of loan being considered. Commercial loans rated as substandard nonaccrual or lower will first have a collateral evaluation completed in accordance with the guidance on impaired loans. Once the collateral evaluation has been completed, a specific allocation of allowance is made based upon the results of the evaluation. The remaining balance remains a nonperforming loan with the original terms and interest rate intact (not restructured). In the event the loan is unsecured, the loan would have been charged-off at the recognition of impairment. Commercial real estate loans rated as impaired will also have an initial collateral evaluation completed in accordance with the guidance on impaired loans. An updated real estate valuation is ordered and the collateral evaluation is modified to reflect any variations in value. A specific allocation of allowance is made for any anticipated collateral shortfall. The remaining balance remains a nonperforming loan with the original terms and interest rate intact (not restructured). The process of charge-off for residential mortgage loans begins upon a loan becoming delinquent for 90 days and not in the process of collection. The existing appraisal is reviewed and a lien search is obtained to determine lien position and any instances of intervening liens. A new appraisal of the property will be ordered if deemed necessary by management and a collateral evaluation is completed. The loan will then be charged down to the value indicated in the evaluation. Consumer loans (including home equity loans and other consumer loans) are recommended for charge-off after reaching delinquency of 90 days and the loan is not in the process of collection. The collateral shortfall of the consumer loan is recommended for charge-off at this point. As noted above, Mid Penn assesses a specific allocation for commercial loans and commercial real estate loans. The remaining balance remains a nonperforming loan with the original terms and interest rate intact (not restructured). In addition, Mid Penn takes a preemptive step when any commercial loan becomes classified under its internal classification system. A preliminary collateral evaluation, in accordance with the guidance on impaired loans, is prepared using the existing collateral information in the loan file. This process allows Mid Penn to review both the credit and documentation files to determine the status of the information needed to make a collateral evaluation. This collateral evaluation is preliminary but allows Mid Penn to determine if any potential collateral shortfalls exist. It is Mid Penn’s policy to obtain updated third party valuations on all impaired loans collateralized by real estate as soon as practically possible of the credit being classified as substandard nonaccrual. Prior to receipt of the updated real estate valuation Mid Penn will use any existing real estate valuation to determine any potential allowance issues; however, no allowance recommendation will be made until such time Mid Penn is in receipt of the updated valuation. The Asset Recovery department employs an electronic tracking system to monitor the receipt of and need for updated appraisals. To date, there have been no material time lapses noted with the above processes. In some instances Mid Penn is not holding real estate as collateral and is relying on business assets (personal property) for repayment. In these circumstances a collateral inspection is performed by Mid Penn personnel to determine an estimated value. The value is based on net book value, as provided by the financial statements, and discounted accordingly based on determinations made by management. Occasionally, Mid Penn will employ an outside service to provide a fair estimate of value based on auction sales or private sales. Management reviews the estimates of these third parties and discounts them accordingly based on management’s judgment, if deemed necessary. For impaired loans with no valuation allowance required, Mid Penn’s practice of obtaining independent third party market valuations on the subject property as soon as practically possible of the credit being placed on nonaccrual status sometimes indicates that the loan to value ratio is sufficient to obviate the need for a specific allocation in spite of significant deterioration in real estate values in Mid Penn’s primary market area. These circumstances are determined on a case by case analysis of the impaired loans. Mid Penn actively monitors the values of collateral on impaired loans. This monitoring may require the modification of collateral values over time or changing circumstances by some factor, either positive or negative, from the original values. All collateral values will be assessed by management at least every 12 months for possible revaluation by an independent third party. An unallocated component is maintained to cover uncertainties that could affect management’s estimate of probable losses. The unallocated component of the allowance reflects the margin of imprecision inherent in the underlying assumptions used in the methodologies for estimating specific and general losses in the portfolio. Large groups of smaller balance homogeneous loans are collectively evaluated for impairment. Accordingly, Mid Penn does not separately identify individual residential mortgage loans, home equity loans and other consumer loans for impairment disclosures, unless such loans are the subject of a troubled debt restructuring agreement. Loans whose terms are modified are classified as troubled debt restructurings if the borrowers have been granted concessions and it is deemed that those borrowers are experiencing financial difficulty. Concessions granted under a troubled debt restructuring generally involve a temporary reduction in interest rate or an extension of a loan’s stated maturity date. Nonaccrual troubled debt restructurings are restored to accrual status if principal and interest payments, under the modified terms, are current for six consecutive months after modification. Loans classified as troubled debt restructurings are designated as impaired. The allowance calculation methodology includes further segregation of loan classes into risk rating categories. The borrower’s overall financial condition, repayment sources, guarantors, and value of collateral, if appropriate, are evaluated annually for commercial loans or when credit deficiencies arise, such as delinquent loan payments. Credit quality risk ratings include regulatory classifications of special mention, substandard, doubtful, and loss. Loans criticized as special mention have potential weaknesses that deserve management’s close attention. If uncorrected, the potential weaknesses may result in deterioration of the repayment prospects. Loans classified substandard have a well-defined weakness or weaknesses that jeopardize the liquidation of the debt. They include loans that are inadequately protected by the current sound net worth and paying capacity of the obligor or of the collateral pledged, if any. Loans classified doubtful have all the weaknesses inherent in loans classified substandard with the added characteristic that collection or liquidation in full, on the basis of current conditions and facts, is highly improbable. Loans classified as a loss are considered uncollectible and are charged to the allowance for loan losses. Any loans not classified as noted above are rated pass. In addition, Federal and State regulatory agencies, as an integral part of their examination process, periodically review the Bank’s allowance for loan and lease losses and may require the Bank to recognize additions to the allowance based on their judgments about information available to them at the time of their examination, which may not be currently available to management. Based on management’s comprehensive analysis of the loan portfolio, management believes the current level of the allowance for loan losses is adequate. Acquired Loans Loans that Mid Penn acquires in connection with business combinations are recorded at fair value with no carryover of the existing related allowance for loan losses. Fair value of the loans involves estimating the amount and timing of principal and interest cash flows expected to be collected on the loans and discounting those cash flows at a market rate of interest. The excess of cash flows expected at acquisition over the estimated fair value is referred to as the accretable discount and is recognized into interest income over the remaining life of the loan. The difference between contractually required payments at acquisition and the cash flows expected to be collected at acquisition is referred to as the nonaccretable discount. These loans are accounted for under the Accounting Standard Codification (“ASC”) 310-30, Loans and Debt Securities Acquired with Deteriorated Credit Quality Loans acquired through business combinations that do meet the specific criteria of ASC 310-30 are individually evaluated each period to analyze expected cash flows. To the extent that the expected cash flows of a loan have decreased due to credit deterioration, Mid Penn establishes an allowance. Loans acquired through business combinations that do not meet the specific criteria of ASC 310-30 are accounted for under ASC 310-20. These loans are initially recorded at fair value, and include credit and interest rate marks associated with acquisition accounting adjustments. Purchase premiums or discounts are subsequently amortized as an adjustment to yield over the estimated contractual lives of the loans. There is no allowance for loan losses established at the acquisition date for acquired performing loans. An allowance for loan losses is recorded for any credit deterioration in these loans subsequent to acquisition. Acquired loans that met the criteria for impaired or nonaccrual of interest prior to the acquisition may be considered performing upon acquisition, regardless of whether the customer is contractually delinquent if Mid Penn expects to fully collect the new carrying value (i.e. fair value) of the loans. As such, Mid Penn may no longer consider the loan to be nonaccrual or nonperforming and may accrue interest on these loans, including the impact of any accretable discount. In addition, charge-offs on such loans would be first applied to the nonaccretable difference portion of the fair value adjustment. (g) Bank Premises and Equipment Land is carried at cost. Buildings, furniture, fixtures, equipment, land improvements, and leasehold improvements are stated at cost less accumulated depreciation. Depreciation is computed by the straight-line method over the estimated useful lives of the assets. Building assets are depreciated using an estimated useful life of five to fifty years. Furniture, fixtures, and equipment are depreciated using an estimated useful life of three to ten years. Land improvements are depreciated over an estimated useful life of ten to twenty years. Leasehold improvements are depreciated using an estimated useful life that is the lesser of the remaining life of the lease or ten to thirty years. Maintenance and normal repairs are charged to expense when incurred, while major additions and improvements are capitalized. Gains and losses on disposals are reflected in current operations. Bank premises and equipment designated as held for sale are carried at the lower of cost or market value. (h) Restricted Investments in Bank Stocks Restricted investments in bank stocks represent required investments in the common stock of correspondent banks. As a member of the FHLB and Atlantic Community Bankers Bank (“ACBB”), the Bank is required to own restricted stock investments in these correspondent banks, which is carried at cost. The total amount of these restricted stock investments was $2,443,000 December 31, 2016 and $4,266,000 at December 31, 2015. This reduction was attributed to the decline in Mid Penn’s FHLB long term advances and its shift from a short-term borrowing to a short-term selling position in 2016. Total dividends received in 2016 and 2015 totaled $135,000 and $250,000, respectively. (i) Foreclosed Assets Held for Sale Foreclosed assets held for sale consist primarily of real estate acquired through, or in lieu of, foreclosure in settlement of debt, and are recorded at fair value less cost to sell at the date of transfer, establishing a new cost basis. Any valuation adjustments required at the date of transfer are charged to the allowance for loan losses. Subsequent to acquisition, foreclosed assets are carried at fair value less costs of disposal, based upon periodic evaluations that consider changes in market conditions and development and disposal costs. Operating results from assets acquired in satisfaction of debt, including rental income less operating costs and gains or losses on the sale of, or the periodic evaluation of foreclosed assets, are recorded in noninterest expense. As of December 31, 2016, Mid Penn had $57,000 of residential real estate held in other real estate owned. There was $426,000 in loans for which formal foreclosure proceedings were in process at December 31, 2016. As of December 31, 2015, Mid Penn had $358,000 of residential real estate held in other real estate owned. There were no loans for which formal foreclosure proceedings were in process at December 31, 2015. (j) Mortgage Servicing Rights Mortgage servicing rights are recognized as assets upon the sale of a mortgage loan. A portion of the cost of the loan is allocated to the servicing right based upon relative fair value. The fair value of servicing rights is based on the present value of estimated future cash flows of mortgages sold, stratified by rate and maturity date. Assumptions that are incorporated in the valuation of servicing rights include assumptions about prepayment speeds on mortgages and the cost to service loans. Servicing rights are reported in core deposit and other intangibles in the Consolidated Balance Sheets and are amortized over the estimated period of future servicing income to be received on the underlying mortgage loans. The carrying amount of mortgage servicing rights was $144,000 and $174,000 at December 31, 2016 and 2015, respectively. Amortization expense is reflected in the Consolidated Statements of Income in other income and was $30,000, $24,000, and $36,000 for the years 2016, 2015, and 2014, respectively. Servicing rights are evaluated for impairment based upon estimated fair value as compared to unamortized book value. (k) Investment in Limited Partnership Mid Penn is a limited partner in a partnership that provides low-income housing in Enola, Pennsylvania. The carrying value of Mid Penn’s investment in the limited partnership was $321,000 at December 31, 2016 and $365,000 at December 31, 2015, net of amortization, using the straight-line method and is reported in other assets on the Consolidated Balance Sheets. Mid Penn’s maximum exposure to loss is limited to the carrying value of its investment. The partnership received $46,000 in low-income housing tax credits during 2016, 20

Mergers and Acquisitions

Mergers and Acquisitions	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Mergers and Acquisitions	(4) Mergers and Acquisitions On March 1, 2015, Phoenix Bancorp, Inc. (“Phoenix”) merged with, and into, Mid Penn, with Mid Penn continuing as the surviving entity. Simultaneously with the consummation of the foregoing merger, Miners Bank (“Miners”), a Pennsylvania-state chartered bank and wholly-owned subsidiary of Phoenix, merged with and into the Bank. As part of this transaction, Phoenix shareholders received either 3.167 shares of the Company’s common stock or $51.60 in cash in exchange for each share of Phoenix common stock. Holders of contingent rights issued by Phoenix received approximately 0.414 shares of the Company’s common stock as settlement of such rights. As a result, the Company issued 723,851 shares of common stock with an acquisition date fair value of approximately $11,292,000, based on the closing stock price of the Company’s common stock on February 27, 2015 of $15.60, and cash of $2,949,000. Including an insignificant amount of cash paid in lieu of fractional shares, the fair value of total consideration paid was $14,241,000. Additionally, as part of this transaction, on March 1, 2015, Mid Penn assumed all of the liabilities and obligations of Phoenix with respect to 1,750 shares of Phoenix’s preferred stock issued to the United States Treasury (“Treasury”) in connection with the Small Business Lending Fund and issued 1,750 shares of the Company’s Senior Non-Cumulative Perpetual Preferred Stock, Series C that had a $1,000 liquidation preference per share (the “SBLF Preferred Shares”), to the Treasury. The SBLF Preferred Shares qualified as Tier 1 Capital and had terms and conditions identical to those shares of preferred stock issued by Phoenix to the Treasury. The assets and liabilities of Miners and Phoenix were recorded on the consolidated balance sheet at their estimated fair value as of March 1, 2015, and their results of operations have been included in the consolidated income statement since that date. Included in the purchase price was goodwill and a core deposit intangible of $2,902,000 and $578,000, respectively. The core deposit intangible will be amortized over a ten-year period using a sum of the year’s digits basis. The goodwill is not taxable and will not be amortized, but will be measured annually for impairment or more frequently if circumstances require. Core deposit intangible amortization expense projected for the next five years beginning in 2017 is estimated to be $86,000, $75,000, $65,000, $54,000, and $44,000 per year, respectively, and $70,000 in total for years after 2021. The allocation of the purchase price is as follows: (Dollars in thousands) Assets acquired: Cash and cash equivalents $ 11,044 Investment securities 11,331 Loans 110,363 Goodwill 2,902 Core deposit and other intangibles 578 Other assets 7,489 Total assets acquired 143,707 Liabilities assumed: Deposits 123,238 FHLB borrowings 3,570 Other liabilities 908 Total liabilities assumed 127,716 Equity acquired: Preferred stock 1,750 Total equity acquired and liabilities assumed 129,466 Consideration paid $ 14,241 Cash paid $ 2,949 Fair value of common stock issued, including replacement equity awards 11,292 The following table summarizes the estimated fair value of the assets acquired and liabilities and equity assumed. (Dollars in thousands) Total purchase price $ 14,241 Net assets acquired: Cash and cash equivalents 11,044 Investment securities 11,331 Restricted stock 509 Loans 110,363 Bank owned life insurance 3,673 Premises and equipment 1,792 Deferred income taxes 503 Accrued interest receivable 388 Core deposit and other intangibles 578 Other assets 624 Deposits (123,238 ) FHLB borrowings (3,570 ) Accrued interest payable (32 ) Other liabilities (876 ) Preferred stock (1,750 ) 11,339 Goodwill $ 2,902 The fair value of the financial assets acquired included loans receivable with a gross amortized cost basis of $112,816,000. The table below illustrates the fair value adjustments made to the amortized cost basis in order to present a fair value of the loans acquired. (Dollars in thousands) Gross amortized cost basis at March 1, 2015 $ 112,816 Market rate adjustment 270 Credit fair value adjustment on pools of homogeneous loans (1,461 ) Credit fair value adjustment on impaired loans (1,262 ) Fair value of purchased loans at March 1, 2015 $ 110,363 The market rate adjustment represents the movement in market interest rates, irrespective of credit adjustments, compared to the stated rates of the acquired loans. The credit adjustment made on pools of homogeneous loans represents the changes in credit quality of the underlying borrowers from the loan inception to the acquisition date. The credit adjustment on impaired loans is derived in accordance with ASC 310-30 and represents the portion of the loan balance that has been deemed uncollectible based on our expectations of future cash flows for each respective loan. The information about the acquired Phoenix loans accounted for under ASC 310-30 as of March 1, 2015 is as follows: (Dollars in thousands) Contractually required principal and interest at acquisition $ 3,548 Contractual cash flows not expected to be collected (nonaccretable discount) (804 ) Expected cash flows at acquisition 2,744 Interest component of expected cash flows (accretable discount) (458 ) Fair value of acquired loans $ 2,286 The following table presents unaudited pro forma information as if the merger between Mid Penn and Phoenix had been completed on January 1, 2014. The pro forma information does not necessarily reflect the results of operations that would have occurred had Mid Penn merged with Phoenix at the beginning of 2014. Supplemental pro forma earnings for 2015 were adjusted to exclude $762,000 of merger related costs incurred for the year ended December 31, 2015; the results for the year ended December 31, 2014 were adjusted to include these charges. The pro forma financial information does not include the impact of possible business model changes, nor does it consider any potential impacts of current market conditions or revenues, expense efficiencies, or other factors. The pro forma data is intended for informational purposes and is not indicative of the future results of operations. (Unaudited) Years Ended (Dollars in thousands, except per share data) 2015 2014 Net interest income after loan loss provision $ 31,454 $ 29,745 Noninterest income 4,152 4,131 Noninterest expense 27,817 26,846 Net income available to common shareholders 5,811 5,259 Net income per common share 1.38 1.25 The amount of total revenue, consisting of interest income plus noninterest income specifically related to Phoenix for the period beginning March 1, 2015, included in the consolidated statements of income of Mid Penn for the year ended December 31, 2015, was $4,244,000. The net income specifically related to Phoenix for the period beginning March 1, 2015, included in the consolidated statements of income of Mid Penn for the year ended December 31, 2015, was $747,000.

Accumulated Other Comprehensive

Accumulated Other Comprehensive (Loss) Income	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive (Loss) Income	(8) Accumulated Other Comprehensive Loss The components of accumulated other comprehensive loss, net of taxes, are as follows: (Dollars in thousands) Unrealized Defined Accumulated Other Balance—June 30, 2017 $ (1,073 ) $ 62 $ (1,011 ) Balance—December 31, 2016 $ (2,919 ) $ 66 $ (2,853 )	(5) Accumulated Other Comprehensive (Loss) Income The components of accumulated other comprehensive (loss) income, net of taxes, are as follows: (Dollars in thousands) Unrealized (Loss) Securities Defined Benefit Plan Liability Accumulated Other Comprehensive (Loss) Income Balance—December 31, 2016 $ (2,919 ) $ 66 $ (2,853 ) Balance—December 31, 2015 $ 1,565 $ 247 $ 1,812

Restrictions on Cash and Due fr

Restrictions on Cash and Due from Bank Accounts	12 Months Ended
	Dec. 31, 2016
Receivables [Abstract]
Restrictions on Cash and Due from Bank Accounts	(6) Restrictions on Cash and Due from Bank Accounts The Bank is required to maintain reserve balances with the Federal Reserve Bank of Philadelphia. There was no required reserve balance at December 31, 2016 and December 31, 2015 because the Bank had sufficient vault cash available.

Investment Securities

Investment Securities	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Securities Financing Transactions Disclosures Abstract
Investment Securities	(2) Investment Securities Securities to be held for indefinite periods, but not intended to be held to maturity, are classified as available-for-sale Realized gains and losses on dispositions are based on the net proceeds and the amortized cost of the securities sold, using the specific identification method. Unrealized gains and losses on investment securities are based on the difference between the amortized cost and fair value of each security as of the respective reporting date. Unrealized gains and losses are credited or charged to other comprehensive income, whereas realized gains and losses flow through Mid Penn’s consolidated statements of income for the respective period. ASC Topic 320, Investments—Debt and Equity Securities In instances when a determination is made that other-than-temporary impairment exists but the investor does not intend to sell the debt security and it is not more likely than not that it will be required to sell the debt security prior to its anticipated recovery, this guidance changes the presentation and amount of the other-than-temporary impairment recognized in the income statement. The other-than-temporary impairment is separated into (a) the amount of the total other-than-temporary impairment related to a decrease in cash flows expected to be collected from the debt security (the credit loss) and (b) the amount of the total other-than-temporary impairment related to all other factors. The amount of the total other-than-temporary impairment related to the credit loss is recognized in earnings. The amount of the total other-than-temporary impairment related to all other factors is recognized in other comprehensive income. Mid Penn had no securities considered by management to be other-than-temporarily impaired as of June 30, 2017, December 31, 2016, or June 30, 2016, and did not record any securities impairment charges in the respective periods ended on these dates. Mid Penn does not consider the securities with unrealized losses on the respective dates to be other-than-temporarily impaired as the unrealized losses were deemed to relate to changes in interest rates, and not erosion of credit quality. The amortized cost, fair value, and unrealized gains and losses on investment securities at June 30, 2017 and December 31, 2016 are as follows: (Dollars in thousands) Amortized Unrealized Unrealized Fair Value June 30, 2017 Available-for-sale U.S. Treasury and U.S. government agencies $ 42,629 $ — $ 858 $ 41,771 Mortgage-backed U.S. government agencies 28,543 3 307 28,239 State and political subdivision obligations 39,539 70 514 39,095 Corporate debt securities 1,100 5 — 1,105 Equity securities 1,168 15 40 1,143 Total available-for-sale 112,979 93 1,719 111,353 Held-to-maturity U.S. Treasury and U.S. government agencies 10,984 24 5 11,003 Mortgage-backed U.S. government agencies 51,248 72 99 51,221 State and political subdivision obligations 8,864 120 9 8,975 Corporate debt securities — — — — Equity securities — — — — Total held-to-maturity 71,096 216 113 71,199 Total $ 184,075 $ 309 $ 1,832 $ 182,552 (Dollars in thousands) Amortized Unrealized Unrealized Fair Value December 31, 2016 Available-for-sale U.S. Treasury and U.S. government agencies $ 48,520 $ 34 $ 1,542 $ 47,012 Mortgage-backed U.S. government agencies 26,181 17 579 25,619 State and political subdivision obligations 61,079 91 2,332 58,838 Corporate debt securities 1,100 — — 1,100 Equity securities 1,168 — 112 1,056 Total available-for-sale $ 138,048 $ 142 $ 4,565 $ 133,625 There were no held-to-maturity Estimated fair values of debt securities are based on quoted market prices, where applicable. If quoted market prices are not available, fair values are based on quoted market prices of comparable instruments, adjusted for differences between the quoted instruments and the instruments being valued. Please refer to Note (4)—Fair Value Measurement Investment securities having a fair value of $126,032,000 at June 30, 2017 and $131,469,000 at December 31, 2016, were pledged to secure public deposits and certain other borrowings. Mid Penn realized gross gains and losses of $77,000 and ($65,000), respectively, on sales of securities available for sale during the three months ended June 30, 2017, while gross gains and losses of $200,000 and ($180,000), respectively, were realized on sales of securities available for sale during the six months ended June 30, 2017. Mid Penn realized gross gains and losses of $450,000 and ($237,000), respectively, on sales of securities available for sale during the six months ended June 30, 2016. The following tables present gross unrealized losses and fair value of investments aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at June 30, 2017 and December 31, 2016. Less Than 12 Months 12 Months or More Total (Dollars in thousands) Number Fair Unrealized Number Fair Unrealized Number Fair Unrealized June 30, 2017 Available-for-sale U.S. Treasury and U.S. government agencies 21 $ 39,077 $ 852 1 $ 2,694 $ 6 22 $ 41,771 $ 858 Mortgage-backed U.S. government agencies 18 26,466 291 1 535 16 19 27,001 307 State and political subdivision obligations 48 24,121 381 7 3,845 133 55 27,966 514 Equity securities 0 — — 1 550 40 1 550 40 Total temporarily impaired available- for-sale securities 87 89,664 1,524 10 7,624 195 97 97,288 1,719 Held-to-maturity U.S. Treasury and U.S. government agencies 2 4,991 5 0 — — 2 4,991 5 Mortgage-backed U.S. government agencies 14 22,879 99 0 — — 14 22,879 99 State and political subdivision obligations 3 1,536 9 0 — — 3 1,536 9 Total temporarily impaired held-to-maturity 19 29,406 113 0 — — 19 29,406 113 Total 106 $ 119,070 $ 1,637 10 $ 7,624 $ 195 116 $ 126,694 $ 1,832 Less Than 12 Months 12 Months or More Total (Dollars in thousands) Number Fair Unrealized Number Fair Unrealized Number Fair Unrealized December 31, 2016 Available-for-sale U.S. Treasury and U.S. government agencies 23 $ 43,698 $ 1,542 0 $ — $ — 23 $ 43,698 $ 1,542 Mortgage-backed U.S. government agencies 18 24,321 579 0 — — 18 24,321 579 State and political subdivision obligations 108 50,582 2,332 0 — — 108 50,582 2,332 Equity securities 0 — — 2 1,056 112 2 1,056 112 Total temporarily impaired available-for-sale 149 $ 118,601 $ 4,453 2 $ 1,056 $ 112 151 $ 119,657 $ 4,565 There were no held-to-maturity Management evaluates securities for other-than-temporary impairment on at least a quarterly basis, and more frequently when economic or market concerns warrant such additional evaluation. Consideration is given to the length of time and the extent to which the fair value has been less than amortized cost and the financial condition and near term prospects of the issuer. In addition, for debt securities, Mid Penn considers (a) whether management has the intent to sell the security, (b) it is more likely than not that management will be required to sell the security prior to its anticipated recovery, and (c) whether management expects to recover the entire amortized cost basis. For equity securities, management considers the intent and ability to hold securities until recovery of unrealized losses. The majority of the investment portfolio is comprised of securities issued by U.S. government agencies and state and political subdivision obligations. For the investment securities with an unrealized loss, Mid Penn has concluded, based on its analysis, that the unrealized losses were primarily caused by the movement of interest rates and not due to an erosion of credit quality of the underlying issuers. At June 30, 2017, the majority of the unrealized losses on available-for-sale held-to-maturity The table below illustrates the maturity distribution of investment securities at amortized cost and fair value as of June 30, 2017. Available-for-sale Held-to-maturity (Dollars in thousands) Amortized Fair Value Amortized Fair June 30, 2017 Due in 1 year or less $ 1,293 $ 1,292 $ — $ — Due after 1 year but within 5 years 20,311 20,178 14,486 14,546 Due after 5 years but within 10 years 47,618 46,801 5,362 5,432 Due after 10 years 14,046 13,700 — — 83,268 81,971 19,848 19,978 Mortgage-backed securities 28,543 28,239 51,248 51,221 Equity securities 1,168 1,143 — — $ 112,979 $ 111,353 $ 71,096 $ 71,199	(7) Investment Securities Securities to be held for indefinite periods, but not intended to be held to maturity, are classified as available for sale and carried at fair value. Securities held for indefinite periods include securities that management intends to use as part of its asset and liability management strategy and that may be sold in response to liquidity needs, changes in interest rates, resultant prepayment risk, and other factors related to interest rate and resultant prepayment risk changes. Realized gains and losses on dispositions are based on the net proceeds and the adjusted book value of the securities sold, using the specific identification method. Unrealized gains and losses on investment securities available for sale are based on the difference between book value and fair value of each security. These gains and losses are credited or charged to other comprehensive income (loss), whereas realized gains and losses flow through Mid Penn’s consolidated statements of income. ASC Topic 320, Investments – Debt and Equity Securities In instances when a determination is made that other-than-temporary impairment exists but the investor does not intend to sell the debt security and it is not more likely than not that it will be required to sell the debt security prior to its anticipated recovery, this guidance changes the presentation and amount of the other-than-temporary impairment recognized in the income statement. The other-than-temporary impairment is separated into (a) the amount of the total other-than-temporary impairment related to a decrease in cash flows expected to be collected from the debt security (the credit loss) and (b) the amount of the total other-than-temporary impairment related to all other factors. The amount of the total other-than-temporary impairment related to the credit loss is recognized in earnings. The amount of the total other-than-temporary impairment related to all other factors is recognized in other comprehensive income (loss). In assessing potential other-than-temporary impairment for equity securities, consideration is given to management’s intent and ability to hold the securities until recovery of unrealized losses. Mid Penn had no other-than-temporary impaired debt or equity securities in 2016, 2015, and 2014. At December 31, 2016 and 2015, amortized cost, fair value, and unrealized gains and losses on investment securities are as follows: (Dollars in thousands) Amortized Unrealized Unrealized Fair December 31, 2016 Available for sale securities: U.S. Treasury and U.S. government agencies $ 48,520 $ 34 $ 1,542 $ 47,012 Mortgage-backed U.S. government agencies 26,181 17 579 25,619 State and political subdivision obligations 61,079 91 2,332 58,838 Corporate debt securities 1,000 — — 1,000 Equity securities 1,268 — 112 1,156 $ 138,048 $ 142 $ 4,565 $ 133,625 (Dollars in thousands) Amortized Unrealized Unrealized Fair December 31, 2015 Available for sale securities: U.S. Treasury and U.S. government agencies $ 26,316 $ 729 $ 55 $ 26,990 Mortgage-backed U.S. government agencies 38,983 49 228 38,804 State and political subdivision obligations 64,780 1,914 77 66,617 Corporate debt securities 2,000 80 10 2,070 Equity securities 1,271 2 33 1,240 $ 133,350 $ 2,774 $ 403 $ 135,721 Estimated fair values of debt securities are based on quoted market prices, where applicable. If quoted market prices are not available, fair values are based on quoted market prices of comparable instruments, adjusted for differences between the quoted instruments and the instruments being valued. Investment securities having a fair value of $131,469,000 at December 31, 2016, and $130,298,000 at December 31, 2015, were pledged primarily to secure public deposits. The following table presents gross unrealized losses and fair value of investments aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at December 31, 2016 and 2015. Less Than 12 Months 12 Months or More Total (Dollars in thousands) December 31, 2016 Number Fair Value Unrealized Number Fair Unrealized Number Fair Value Unrealized Available for sale securities: U.S. Treasury and U.S. government agencies 23 $ 43,698 $ 1,542 0 $ — $ — 23 $ 43,698 $ 1,542 Mortgage-backed U.S. government agencies 18 24,321 579 0 — — 18 24,321 579 State and political subdivision obligations 108 50,582 2,332 0 — — 108 50,582 2,332 Equity securities 0 — — 2 1,056 112 2 1,056 112 Total temporarily impaired available for sale securities 149 $ 118,601 $ 4,453 2 $ 1,056 $ 112 151 $ 119,657 $ 4,565 Less Than 12 Months 12 Months or More Total (Dollars in thousands) December 31, 2015 Number Fair Unrealized Number Fair Unrealized Number Fair Unrealized Available for sale securities: U.S. Treasury and U.S. government agencies 6 $ 6,259 $ 43 2 $ 1,383 $ 12 8 $ 7,642 $ 55 Mortgage-backed U.S. government agencies 13 12,759 124 11 6,282 104 24 19,041 228 State and political subdivision obligations 9 4,041 32 3 1,631 45 12 5,672 77 Corporate debt securities 1 990 10 0 — — 1 990 10 Equity securities 0 — — 2 615 33 2 615 33 Total temporarily impaired available for sale securities 29 $ 24,049 $ 209 18 $ 9,911 $ 194 47 $ 33,960 $ 403 Management evaluates securities for other-than-temporary impairment on a quarterly basis; and more frequently when economic or market concerns warrant such evaluation. Consideration is given to the length of time and the extent to which the fair value has been less than cost, and the financial condition and near term prospects of the issuer. In addition, for debt securities, Mid Penn considers (a) whether management has the intent to sell the security, (b) it is more likely than not that management will be required to sell the security prior to its anticipated recovery, and (c) whether management expects to recover the entire amortized cost basis. For equity securities, management considers the intent and ability to hold securities until recovery of unrealized losses. The majority of the investment portfolio is comprised of mortgage-backed U.S. government agencies and state and political subdivision obligations. For the investment securities with an unrealized loss, Mid Penn has concluded, based on its analysis, that the unrealized losses in the investments are primarily caused by the movement of interest rates, and the contractual terms of these investments do not permit the issuer to settle the securities at a price less than the par value of the investment. At December 31, 2016, Mid Penn had 149 debt securities and 2 equity securities with unrealized losses totaling $4,565,000 that depreciated 3.82% from their collective amortized cost basis. At December 31, 2016, the majority of the unrealized losses on securities in an unrealized loss position were attributed to state and political subdivision obligations and U.S. Treasury and government agencies. At December 31, 2015, Mid Penn had 45 debt securities and 2 equity securities with unrealized losses totaling $403,000 that depreciated 1.19% from their amortized cost basis. At December 31, 2015, the majority of the unrealized losses on securities in an unrealized loss position were attributed to mortgage-backed U.S. government agencies. Because Mid Penn does not intend to sell these investments and it is not likely it will be required to sell these investments before a recovery of fair value, which may be maturity, Mid Penn does not consider the securities with unrealized losses to be other-than-temporarily impaired as losses relate to changes in interest rates and not erosion of credit quality. During 2016, Mid Penn realized gross gains on the sales of securities available for sale of $1,927,000 on 102 debt securities. Mid Penn also realized $881,000 in gross losses on the sales of 56 debt securities available for sale during 2016. Mid Penn realized gross gains of $325,000 and $168,000 on sales of securities available for sale during 2015 and 2014, respectively, while no gross losses were realized in 2015 and 2014. The table below is the maturity distribution of investment securities at amortized cost and fair value at December 31, 2016. December 31, 2016 (Dollars in thousands) Amortized Fair Value Due in 1 year or less $ 1,293 $ 1,305 Due after 1 year but within 5 years 19,656 19,471 Due after 5 years but within 10 years 66,084 63,895 Due after 10 years 23,566 22,179 110,599 106,850 Mortgage-backed securities 26,181 25,619 Equity securities 1,268 1,156 $ 138,048 $ 133,625

Loans and Allowance for Loan an

Loans and Allowance for Loan and Lease Losses	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Loans and Allowance for Loan and Lease Losses	(3) Loans and Allowance for Loan and Lease Losses Loans receivable that management has the intent and ability to hold for the foreseeable future or until maturity or payoff are stated at their outstanding unpaid principal balances, net of an allowance for loan losses and any deferred fees or costs. Interest income is accrued on the unpaid principal balance. Loan origination fees, net of certain direct origination costs, are deferred and recognized as an adjustment of the yield (interest income) of the related loans, generally being amortized over the contractual life of the loan. Premiums and discounts on purchased loans are amortized as adjustments to interest income using the effective yield method. The loan portfolio is segmented into commercial and consumer loans. Commercial loans consist of the following classes: commercial and industrial, commercial real estate, commercial real estate-construction and lease financing. Consumer loans consist of the following classes: residential mortgage loans, home equity loans and other consumer loans. For all classes of loans, the accrual of interest generally is discontinued when the contractual payment of principal or interest has become 90 days or more past due, or management has serious doubts about further collectability of principal or interest even though the loan is currently performing. A loan past due 90 days or more may remain on accrual status if it is in the process of collection and is either guaranteed or well secured. When a loan is placed on nonaccrual status, unpaid interest is credited to income. Interest received on nonaccrual loans, including impaired loans, is either applied against principal or reported as interest income, according to management’s judgment as to the collectability of principal. Nonaccrual loans may be restored to accrual status when the obligation is brought current, has performed in accordance with the contractual terms for a reasonable period of time (generally, at least nine consecutive months) and the ultimate collectability of the total contractual principal and interest is no longer in doubt. The past due status of all classes of loans receivable is determined based on contractual due dates for loan payments. Commercial and industrial Mid Penn originates commercial and industrial loans. Most of the Bank’s commercial and industrial loans have been extended to finance local and regional businesses and include short-term loans to finance machinery and equipment purchases, inventory, and accounts receivable. Commercial loans also involve the extension of revolving credit for a combination of equipment acquisitions and working capital in expanding companies. The maximum term for loans extended on machinery and equipment is based on the projected useful life of such machinery and equipment. Generally, the maximum term on non-mortgage loan-to-value Commercial and industrial loans typically are made on the basis of the borrower’s ability to make repayment from the cash flow of the borrower’s business. As a result, the availability of funds for the repayment of commercial business loans may be substantially dependent on the success of the business itself, which, in turn, is likely to be dependent upon the general economic environment. Mid Penn’s commercial and industrial loans are usually, but not always, secured by business assets and personal guarantees. However, the collateral securing the loans may depreciate over time, may be difficult to appraise, and may fluctuate in value based on the success of the business. Commercial real estate and commercial real estate—construction Commercial real estate and commercial real estate construction loans generally present a higher level of risk than loans secured by one-to-four Residential mortgage Mid Penn offers a wide array of residential mortgage loans for both permanent structures and those under construction. The Bank’s residential mortgage originations are secured primarily by properties located in its primary market and surrounding areas. Residential mortgage loans have terms up to a maximum of 30 years and with loan-to-value In underwriting residential mortgage loans, the Bank evaluates both the borrower’s ability to make monthly payments and the value of the property securing the loan. Most properties securing real estate loans made by Mid Penn are appraised by independent fee appraisers. The Bank generally requires borrowers to obtain title insurance and fire and property insurance (including flood insurance, if necessary) in an amount not less than the amount of the loan. Real estate loans originated by the Bank generally contain a “due on sale” clause allowing the Bank to declare the unpaid principal balance due and payable upon the sale of the security property. The Bank underwrites residential mortgage loans to the standards established by the secondary mortgage market, i.e., Fannie Mae, Ginnie Mae, Freddie Mac, or Pennsylvania Housing Finance Agency standards, with the intention of selling the majority of residential mortgages originated into the secondary market. In the event that the facts and circumstances surrounding a residential mortgage application do not meet all underwriting conditions of the secondary mortgage market, the Bank will evaluate the failed conditions and evaluate the potential risk of holding the residential mortgage in the Bank’s portfolio rather than rejecting the loan request. In the event that the loan is held in the Bank’s portfolio, the interest rate on the residential mortgage would be increased to compensate for the added portfolio risk. Consumer, including home equity Mid Penn offers a variety of secured consumer loans, including home equity, automobile, and deposit secured loans. In addition, the Bank offers other secured and unsecured consumer loans. Most consumer loans are originated in Mid Penn’s primary market and surrounding areas. The largest component of Mid Penn’s consumer loan portfolio consists of fixed rate home equity loans and variable rate home equity lines of credit. Substantially all home equity loans and lines of credit are secured by junior lien mortgages on principal residences. The Bank will lend amounts, which, together with all prior liens, typically may be up to 85 percent of the appraised value of the property securing the loan. Home equity term loans may have maximum terms up to 20 years while home equity lines of credit generally have maximum terms of five years. Consumer loan terms vary according to the type and value of collateral, length of contract and creditworthiness of the borrower. The underwriting standards employed by the Bank for consumer loans include an application, a determination of the applicant’s payment history on other debts, and an assessment of ability to meet existing obligations and payments on the proposed loan. Although creditworthiness of the applicant is a primary consideration, the underwriting process also includes a comparison of the value of the collateral, if any, in relation to the proposed loan amount. Consumer loans may entail greater credit risk than do residential mortgage loans, particularly in the case of consumer loans which are unsecured or are secured by rapidly depreciable assets, such as automobiles or recreational equipment. In such cases, any repossessed collateral for a defaulted consumer loan may not provide an adequate source of repayment of the outstanding loan balance. In addition, consumer loan collections are dependent on the borrower’s continuing financial stability, and thus are more likely to be affected by adverse personal circumstances. Furthermore, the application of various federal and state laws, including bankruptcy and insolvency laws, may limit the amount that can be recovered on such loans. Junior liens inherently have more credit risk by virtue of the fact that another financial institution may have a higher security position in the case of foreclosure liquidation of collateral to extinguish the debt. Generally, foreclosure actions could become more prevalent if the real estate market weakens and property values deteriorate. Allowance for Loan and Lease Losses The allowance for credit losses (“allowance”) consists of (i) the allowance for loan and lease losses, and (ii) the reserve for unfunded lending commitments. The allowance for loan and lease losses represents management’s estimate of losses inherent in the loan portfolio as of the balance sheet date and is recorded as a reduction to loans. The reserve for unfunded lending commitments represents management’s estimate of losses inherent in its unfunded loan commitments and is recorded in other liabilities on the consolidated balance sheet. The reserve for unfunded lending commitments was $127,000 at June 30, 2017 and $120,000 at December 31, 2016. The allowance is increased by the provision for loan and lease losses, and decreased by charge-offs, net of recoveries. Loans deemed to be uncollectible are charged against the allowance, and subsequent recoveries, if any, are credited to the allowance. All, or part, of the principal balance of loans are charged off to the allowance as soon as it is determined that the repayment of all, or part, of the principal balance is highly unlikely. Non-residential The allowance is maintained at a level considered by management to be adequate to provide for losses that can be reasonably anticipated. Management performs a monthly evaluation of the adequacy of the allowance. The allowance is based on Mid Penn’s past loan loss experience, known and inherent risks in the portfolio, adverse situations that may affect the borrower’s ability to repay, the estimated value of any underlying collateral, composition of the loan portfolio, current economic conditions, and other relevant factors. This evaluation is inherently subjective as it requires material estimates that may be susceptible to significant revision as more information becomes available. The allowance consists of specific, general and unallocated components. The specific component relates to loans that are classified as impaired. For loans that are classified as impaired, an allowance is established when the discounted cash flows, collateral value, or observable market price of the impaired loan is lower than the carrying value of that loan. The general component covers pools of loans by loan class including commercial loans not considered impaired, as well as smaller balance homogeneous loans, such as residential real estate, home equity and other consumer loans. These pools of loans are evaluated for loss exposure based upon historical loss rates for each of these categories of loans, adjusted for qualitative factors. These qualitative risk factors include changes in economic conditions, fluctuations in loan quality measures, changes in collateral values, changes in the experience of the lending staff and loan review systems, changes in lending policies and procedures (including underwriting standards), changes in the mix and volume of loans originated, the effect of other external factors such as competition and legal and regulatory requirements on the level of estimated credit losses in the existing loan portfolio, shifting industry or portfolio concentrations, and other relevant factors. Each factor is assigned a value to reflect improving, stable or declining conditions based on management’s best judgment using relevant information available at the time of the evaluation. Adjustments to the factors are supported through documentation of changes in conditions in a narrative accompanying the allowance for loan loss calculation. The unallocated component of the allowance for loan and lease losses covers several considerations that are not specifically measureable through either the specific and general components. For example, we believe that we could face increasing credit risks and uncertainties, not yet reflected in recent historical losses or qualitative factor assessments, associated with unpredictable changes in economic growth or business conditions in our markets or for certain industries in which we have commercial loan borrowers, or unanticipated stresses to the values of real estate held as collateral. Any or all of these additional issues can adversely affect our borrowers’ ability to timely repay their loans. Additionally, we have experienced continued strong commercial loan growth, including growth in newer markets where we have less of a loss history. Also, the unallocated component allocation recognizes the inherent imprecision in our allowance for loan and lease loss methodology, or any alternative methodology, for estimating specific and general loan losses, including the unpredictable timing and amounts of charge-offs, the fact that historical loss averages don’t necessarily correlate to future loss trends, and unexpected changes to specific-credit or general portfolio future cash flows and collateral values which could negatively impact unimpaired portfolio loss factors. Mid Penn generally considers a commercial loan (consisting of commercial and industrial, commercial real estate, commercial real estate-construction, and lease financing loan classes) to be impaired when it becomes 90 days or more past due and not in the process of collection or sooner when it is probable that Mid Penn will be unable to collect all contractual principal and interest due. This methodology assumes the borrower cannot or will not continue to make additional payments. At that time the loan would generally be considered collateral dependent as the discounted cash flow method would generally indicate no operating income available for evaluating the collateral position; therefore, most impaired loans are deemed to be collateral dependent. In addition, Mid Penn’s rating system assumes any loans classified as nonaccrual, included in the substandard rating, to be impaired, and most of these loans are considered collateral dependent; therefore, most of Mid Penn’s impaired loans, whether reporting a specific allocation or not, are considered collateral dependent. Mid Penn evaluates loans for charge-off charge-off charged-off charge-off charge-off As noted above, Mid Penn assesses a specific allocation for commercial loans and commercial real estate loans. The remaining balance remains a nonperforming loan with the original terms and interest rate intact (not restructured). In addition, Mid Penn takes a preemptive step when any commercial loan becomes classified under its internal classification system. A preliminary collateral evaluation, in accordance with the guidance on impaired loans, is prepared using the existing collateral information in the loan file. This process allows Mid Penn to review both the credit and documentation files to determine the status of the information needed to make a collateral evaluation. This collateral evaluation is preliminary but allows Mid Penn to determine if any potential collateral shortfalls exist. It is Mid Penn’s policy to obtain updated third party valuations on all impaired loans collateralized by real estate as soon as practically possible of the credit being classified as substandard nonaccrual. Prior to receipt of the updated real estate valuation Mid Penn will use any existing real estate valuation to determine any potential allowance issues; however, no allowance recommendation will be made until such time Mid Penn is in receipt of the updated valuation. The Asset Recovery department employs an electronic tracking system to monitor the receipt of and need for updated appraisals. To date, there have been no material time lapses noted with the above processes. In some instances Mid Penn is not holding real estate as collateral and is relying on business assets (personal property) for repayment. In these circumstances a collateral inspection is performed by Mid Penn personnel to determine an estimated value. The value is based on net book value, as provided by the financial statements, and discounted accordingly based on determinations made by management. Occasionally, Mid Penn will employ an outside service to provide a fair estimate of value based on auction sales or private sales. Management reviews the estimates of these third parties and discounts them accordingly based on management’s judgment, if deemed necessary. For impaired loans with no valuation allowance required, Mid Penn’s practice of obtaining independent third party market valuations on the subject property as soon as practically possible of the credit being placed on nonaccrual status sometimes indicates that the loan to value ratio is sufficient to obviate the need for a specific allocation in spite of significant deterioration in real estate values in Mid Penn’s primary market area. These circumstances are determined on a case by case analysis of the impaired loans. Mid Penn actively monitors the values of collateral on impaired loans. This monitoring may require the modification of collateral values over time or changing circumstances by some factor, either positive or negative, from the original values. All collateral values will be assessed by management at least every 12 months for possible revaluation by an independent third party. Large groups of smaller balance homogeneous loans are collectively evaluated for impairment. Accordingly, Mid Penn does not separately identify individual residential mortgage loans, home equity loans and other consumer loans for impairment disclosures, unless such loans are the subject of a troubled debt restructuring agreement. Loans whose terms are modified are classified as troubled debt restructurings if the borrowers have been granted concessions and it is deemed that those borrowers are experiencing financial difficulty. Concessions granted under a troubled debt restructuring generally involve a temporary reduction in interest rate or an extension of a loan’s stated maturity date. Nonaccrual troubled debt restructurings are restored to accrual status if principal and interest payments, under the modified terms, are current for nine consecutive months after modification. Loans classified as troubled debt restructurings are designated as impaired. The allowance calculation methodology includes further segregation of loan classes into risk rating categories. The borrower’s overall financial condition, repayment sources, guarantors, and value of collateral, if appropriate, are evaluated annually for commercial loans or when credit deficiencies arise, such as delinquent loan payments. Credit quality risk ratings include regulatory classifications of special mention, substandard, doubtful, and loss. Loans criticized as special mention have potential weaknesses that deserve management’s close attention. If uncorrected, the potential weaknesses may result in deterioration of the repayment prospects. Loans classified substandard have a well-defined weakness or weaknesses that jeopardize the liquidation of the debt. They include loans that are inadequately protected by the current sound net worth and paying capacity of the obligor or of the collateral pledged, if any. Loans classified doubtful have all the weaknesses inherent in loans classified substandard with the added characteristic that collection or liquidation in full, on the basis of current conditions and facts, is highly improbable. Loans classified as a loss are considered uncollectible and are charged to the allowance for loan losses. Any loans not classified as noted above are rated pass. In addition, Federal and State regulatory agencies, as an integral part of their examination process, periodically review the Bank’s allowance and may require the Bank to recognize additions to the allowance based on their judgments about information available to them at the time of their examination, which may not be currently available to management. Based on management’s comprehensive analysis of the loan portfolio, management believes the current level of the allowance for loan losses is adequate. Acquired Loans Loans that Mid Penn acquires in connection with business combinations are recorded at fair value with no carryover of the existing related allowance for loan losses. Fair value of the loans involves estimating the amount and timing of principal and interest cash flows expected to be collected on the loans and discounting those cash flows at a market rate of interest. The excess of cash flows expected at acquisition over the estimated fair value is referred to as the accretable discount and is recognized into interest income over the remaining life of the loan. The difference between contractually required payments at acquisition and the cash flows expected to be collected at acquisition is referred to as the nonaccretable discount. These loans are accounted for under the ASC 310-30, Loans and Debt Securities Acquired with Deteriorated Credit Quality. Loans acquired through business combinations that meet the specific criteria of ASC 310-30 Loans acquired through business combinations that do not meet the specific criteria of ASC 310-30 310-20. Acquired loans that met the criteria for impaired or nonaccrual of interest prior to the acquisition may be considered performing upon acquisition, regardless of whether the customer is contractually delinquent if Mid Penn expects to fully collect the new carrying value (i.e. fair value) of the loans. As such, Mid Penn may no longer consider the loan to be nonaccrual or nonperforming and may accrue interest on these loans, including the impact of any accretable discount. In addition, charge-offs on such loans would be first applied to the nonaccretable difference portion of the fair value adjustment. The classes of the loan portfolio, summarized by the pass rating (net of deferred fees and costs of $435,000 as of June 30, 2017 and $196,000 as of December 31, 2016), and the classified ratings of special mention, substandard, and doubtful within Mid Penn’s internal risk rating system as of June 30, 2017 and December 31, 2016, are as follows: (Dollars in thousands) Pass Special Mention Substandard Doubtful Total June 30, 2017 Commercial and industrial $ 175,700 $ 4,385 $ 1,283 $ — $ 181,368 Commercial real estate 473,078 1,757 7,306 — 482,141 Commercial real estate—construction 52,543 191 571 — 53,305 Lease financing 307 — — — 307 Residential mortgage 101,186 102 1,349 — 102,637 Home equity 38,154 124 393 — 38,671 Consumer 3,878 — — — 3,878 $ 844,846 $ 6,559 $ 10,902 $ — $ 862,307 (Dollars in thousands) Pass Special Mention Substandard Doubtful Total December 31, 2016 Commercial and industrial $ 170,780 $ 937 $ 801 $ — $ 172,518 Commercial real estate 437,592 1,683 7,249 — 446,524 Commercial real estate—construction 52,888 202 1,286 — 54,376 Lease financing 425 — — — 425 Residential mortgage 97,994 107 1,356 — 99,457 Home equity 37,242 142 224 — 37,608 Consumer 3,016 — — — 3,016 $ 799,937 $ 3,071 $ 10,916 $ — $ 813,924 Impaired loans by loan portfolio class as of June 30, 2017 and December 31, 2016 are summarized as follows: June 30, 2017 December 31, 2016 (Dollars in thousands) Recorded Unpaid Related Recorded Unpaid Related With no related allowance recorded Commercial and industrial $ — $ 18 $ — $ 4 $ 9 $ — Commercial real estate: Commercial real estate 900 1,390 — 726 1,792 — Acquired with credit deterioration 573 573 — 842 842 — Commercial real estate—construction 331 334 618 618 Residential mortgage: Residential mortgage 902 931 — 848 882 — Acquired with credit deterioration 324 324 — 389 389 — Home equity 327 369 — 111 129 — With an allowance recorded Commercial and industrial $ — $ — $ — $ 56 $ 62 $ 6 Commercial real estate 2,751 2,915 893 2,520 2,646 711 Commercial real estate—construction 240 242 70 242 242 72 Residential mortgage 66 68 66 68 68 68 Home equity — — — 29 49 1 Total Impaired Loans Commercial and industrial $ — $ 18 $ — $ 60 $ 71 $ 6 Commercial real estate 4,224 4,878 893 4,088 5,280 711 Commercial real estate—construction 571 576 70 860 860 72 Residential mortgage 1,292 1,323 66 1,305 1,339 68 Home equity 327 369 — 140 178 1 The average recorded investment of impaired loans and related interest income recognized for the three and six months ended June 30, 2017 and 2016 are summarized as follows: Three Months Ended June 30, 2017 June 30, 2016 (Dollars in thousands) Average Interest Average Interest With no related allowance recorded Commercial and industrial $ 36 $ — $ 11 $ — Commercial real estate: Commercial real estate 644 — 960 — Acquired with credit deterioration 644 110 943 — Commercial real estate—construction 473 — — — Lease financing — Residential mortgage: Residential mortgage 860 7 831 7 Acquired with credit deterioration 326 2 377 Home equity: 66 — Home equity 90 — — — Acquired with credit deterioration — — — — Consumer — — — — With an allowance recorded Commercial and industrial $ — $ — $ 59 $ — Commercial real estate 2,792 — 2,201 — Commercial real estate—construction 240 — — — Lease financing — — — — Residential mortgage 66 — — — Home equity — — 17 — Consumer — — — — Total Impaired Loans Commercial and industrial $ 36 $ — $ 70 $ — Commercial real estate 4,080 110 4,104 — Commercial real estate—construction 713 — — — Lease financing — — — — Residential mortgage 1,252 9 1,208 7 Home equity 90 — 83 — Six Months Ended June 30, 2017 June 30, 2016 (Dollars in thousands) Average Interest Average Interest With no related allowance recorded Commercial and industrial $ 18 $ — $ 14 $ — Commercial real estate: Commercial real estate 524 279 1,001 — Acquired with credit deterioration 738 110 934 — Commercial real estate—construction 313 — — — Lease financing — — — — Residential mortgage: Residential mortgage 843 18 777 9 Acquired with credit deterioration 350 — 375 4 Home equity 101 2 53 — Consumer — With an allowance recorded Commercial and industrial $ — $ — $ 61 $ — Commercial real estate 2,660 — 1,851 — Commercial real estate—construction 144 — — — Lease financing — — — — Residential mortgage 40 — — — Home equity — — 19 — Consumer — — — — Total Impaired Loans Commercial and industrial $ 18 $ — $ 75 $ — Commercial real estate 3,922 389 3,786 — Commercial real estate—construction 457 — — — Lease financing — — — — Residential mortgage 1,233 18 1,152 13 Home equity 101 2 72 — Nonaccrual loans by loan portfolio class as of June 30, 2017 and December 31, 2016 are summarized as follows: (Dollars in thousands) June 30, 2017 December 31, 2016 Commercial and industrial $ — $ 4 Commercial real estate 3,630 2,939 Commercial real estate—construction 571 860 Residential mortgage 690 715 Home equity 327 140 $ 5,218 $ 4,658 The performance and credit quality of the loan portfolio is also monitored by analyzing the age of the loans receivable as determined by the length of time a recorded payment is past due. The classes of the loan portfolio summarized by the past due status as of June 30, 2017 and December 31, 2016 are summarized as follows: (Dollars in thousands) 30-59 60-89 Greater Total Current Total Loans June 30, 2017 Commercial and industrial $ 101 $ 4,083 $ — $ 4,184 $ 177,184 $ 181,368 $ — Commercial real estate: Commercial real estate 250 43 2,502 2,795 478,773 481,568 — Acquired with credit deterioration 516 — 57 573 — 573 57 Commercial real estate—construction 371 120 451 942 52,363 53,305 — Lease financing — — — — 307 307 — Residential mortgage: Residential mortgage 174 — 299 473 101,840 102,313 — Acquired with credit deterioration 32 — 226 258 66 324 — Home equity 13 — 298 311 38,360 38,671 — Consumer — — — — 3,878 3,878 — Total $ 1,457 $ 4,246 $ 3,833 $ 9,536 $ 852,771 $ 862,307 $ 57 (Dollars in thousands) 30-59 60-89 Greater Total Current Total Loans December 31, 2016 Commercial and industrial $ 164 $ 12 $ 4 $ 180 $ 172,338 $ 172,518 $ — Commercial real estate: Commercial real estate 475 — 1,004 1,479 444,203 445,682 — Acquired with credit deterioration — — 59 59 783 842 59 Commercial real estate—construction — 404 84 488 53,888 54,376 — Lease financing — — — — 425 425 — Residential mortgage: Residential mortgage 548 124 237 909 98,159 99,068 — Acquired with credit deterioration — — 238 238 151 389 — Home equity 33 13 125 171 37,437 37,608 — Consumer — — — — 3,016 3,016 — Total $ 1,220 $ 553 $ 1,751 $ 3,524 $ 810,400 $ 813,924 $ 59 The following tables summarize the allowance and recorded investments in loans receivable. (Dollars in thousands) Commercial Commercial Commercial Lease Residential Home Consumer Unallocated Total As of, and for the three months ended, June 30, 2017 Allowance for loan and lease losses: Beginning balance, April 1, 2017 $ 1,630 $ 4,715 $ 101 $ 1 $ 532 $ 364 $ 3 $ 274 $ 7,620 Charge-offs — (30 ) — — — — (10 ) — (40 ) Recoveries 3 22 — — 2 5 1 — 33 Provisions (5 ) 274 39 — 5 35 10 (258 ) 100 Ending balance, June 30, 2017 $ 1,628 $ 4,981 $ 140 $ 1 $ 539 $ 404 $ 4 $ 16 $ 7,713 (Dollars in thousands) Commercial Commercial Commercial Lease Residential Home Consumer Unallocated Total As of, and for the six months ended, June 30, 2017 Allowance for loan and lease losses: Beginning balance, January 1, 2017 $ 1,580 $ 4,323 $ 144 $ 1 $ 541 $ 379 $ 3 $ 212 $ 7,183 Charge-offs (12 ) (30 ) — — (18 ) — (16 ) — (76 ) Recoveries 7 361 — — 4 5 4 — 381 Provisions 53 327 (4 ) — 12 20 13 (196 ) 225 Ending balance, June 30, 2017 1,628 4,981 140 1 539 404 4 16 7,713 Ending balance: individually evaluated for impairment — 893 70 — 66 — — — 1,029 Ending balance: collectively evaluated for impairment $ 1,628 $ 4,088 $ 70 $ 1 $ 473 $ 404 $ 4 $ 16 $ 6,684 Loans receivables: Ending balance $ 181,368 $ 482,141 $ 53,305 $ 307 $ 102,637 $ 38,671 $ 3,878 $ — $ 862,307 Ending balance: individually evaluated for impairment — 3,651 571 — 968 327 — — 5,517 Ending balance: acquired with credit deterioration — 573 — — 324 — — — 897 Ending balance: collectively evaluated for impairment $ 181,368 $ 477,917 $ 52,734 $ 307 $ 101,345 $ 38,344 $ 3,878 $ — $ 855,893 (Dollars in thousands) Commercial Commercial Commercial Lease Residential Home Consumer Unallocated Total As of, and for the three months ended, June 30, 2016 Allowance for loan and lease losses: Beginning balance, April 1, 2016 $ 1,427 $ 3,777 $ 119 $ 1 $ 516 $ 303 $ 9 $ 287 $ 6,439 Charge-offs — (54 ) — — — (25 ) (7 ) — (86 ) Recoveries 1 136 — — 25 — 2 — 164 Provisions (56 ) 382 1 — (20 ) 47 5 36 395 Ending balance, June 30, 2016 $ 1,372 $ 4,241 $ 120 $ 1 $ 521 $ 325 $ 9 $ 323 $ 6,912 (Dollars in thousands) Commercial Commercial Commercial Lease Residential Home Consumer Unallocated Total As of, and for the six months ended, June 30, 2016 Allowance for loan and lease losses: Beginning balance, January 1, 2016 $ 1,393 $ 3,552 $ 153 $ 1 $ 534 $ 317 $ 12 $ 206 $ 6,168 Charge-offs — (150 ) — — — (25 ) (10 ) — (185 ) Recoveries 2 161 — — 25 — 6 — 194 Provisions (23 ) 678 (33 ) — (38 ) 33 1 117 735 Ending balance, June 30, 2016 1,372 4,241 120 1 521 325 9 323 6,912 Ending balance: individually evaluated for impairment 3 769 — — — 2 — — 774 Ending balance: collectively evaluated for impairment $ 1,369 $ 3,472 $ 120 $ 1 $ 521 $ 323 $ 9 $ 323 $ 6,138 Loans receivables: Ending balance $ 160,278 $ 410,786 $ 56,074 $ 565 $ 103,822 $ 34,579 $ 3,049 $ — $ 769,153 Ending balance: individually evaluated for impairment 68 3,657 — — 824 81 — — 4,630 Ending balance: acquired with credit deterioration — 951 — — 370 — — — 1,321 Ending balance: collectively evaluated for impairment $ 160,210 $ 406,178 $ 56,074 $ 565 $ 102,628 $ 34,498 $ 3,049 $ — $ 763,202 (Dollars in thousands) Commercial Commercial Commercial Lease Residential Home Consumer Unallocated Total December 31, 2016 Allowance for loan and lease losses: Ending balance $ 1,580 $ 4,323 $ 144 $ 1 $ 541 $ 379 $ 3 $ 212 $ 7,183 Ending balance: individually evaluated for impairment 6 711 72 — 68 1 — — 858 Ending balance: collectively evaluated for impairment $ 1,574 $ 3,612 $ 72 $ 1 $ 473 $ 378 $ 3 $ 212 $ 6,325 Loans receivable: Ending balance $ 172,518 $ 446,524 $ 54,376 $ 425 $ 99,457 $ 37,608 $ 3,016 $ — $ 813,924 Ending balance: individually evaluated for impairment 60 3,246 860 — 916 140 — — 5,222 Ending balance: acquired with credit deterioration — 842 — — 389 — — — 1,231 Ending balance: collectively evaluated for impairment $ 172,458 $ 442,436 $ 53,516 $ 425 $ 98,152 $ 37,468 $ 3,016 $ — $ 807,471 The recorded investments in troubled debt restructured loans at June 30, 2017 and December 31, 2016 are as follows: (Dollars in thousands) Pre-Modification Post-Modification Recorded Investment June 30, 2017 Commercial real estate $ 3,457 $ 4,003 $ 2,407 Residential mortgage 759 743 623 $4,216 $4,746 $3,030 (Dollars in thousands) Pre-Modification Post-Modification Recorded Investment Decem	(8) Loans and Allowance for Loan and Lease Losses The classes of the loan portfolio, summarized by the aggregate pass rating, net of deferred fees and costs of $196,000 and $178,000 as of December 31, 2016 and 2015, respectively, and the classified ratings of special mention, substandard, and doubtful within Mid Penn’s internal risk rating system as of December 31, 2016 and 2015, are noted below: (Dollars in thousands) December 31, 2016 Pass Special Mention Substandard Doubtful Total Commercial and industrial $ 170,780 $ 937 $ 801 $ — $ 172,518 Commercial real estate 437,592 1,683 7,249 — 446,524 Commercial real estate—construction 52,888 202 1,286 — 54,376 Lease financing 425 — — — 425 Residential mortgage 97,994 107 1,356 — 99,457 Home equity 37,242 142 224 — 37,608 Consumer 3,016 — — 3,016 $ 799,937 $ 3,071 $ 10,916 $ — $ 813,924 (Dollars in thousands) December 31, 2015 Pass Special Mention Substandard Doubtful Total Commercial and industrial $ 158,302 $ 1,289 $ 670 $ — $ 160,261 Commercial real estate 359,859 2,088 7,517 — 369,464 Commercial real estate—construction 65,665 2,403 — — 68,068 Lease financing 727 — — — 727 Residential mortgage 101,507 475 1,361 — 100,665 Home equity 32,928 261 222 — 33,411 Consumer 3,917 — — — 3,917 $ 722,905 $ 6,516 $ 9,770 $ — $ 736,513 Impaired loans by loan portfolio class as of December 31, 2016 and 2015 are summarized as follows: December 31, 2016 December 31, 2015 (Dollars in thousands) Recorded Unpaid Related Recorded Unpaid Related With no related allowance recorded: Commercial and industrial: Commercial and industrial $ 4 $ 9 $ — $ 14 $ 49 $ — Commercial real estate: Commercial real estate 726 1,792 — 1,023 2,020 — Acquired with credit deterioration* 842 842 — 931 931 — Commercial real estate—construction: Commercial real estate—construction 618 618 — — — — Residential mortgage: Residential mortgage 848 882 — 1,329 1,434 — Acquired with credit deterioration* 389 389 — 400 400 — Home equity: Home equity 111 129 — 115 137 — With an allowance recorded: Commercial and industrial $ 56 $ 62 $ 6 $ 113 $ 128 $ 51 Commercial real estate 2,520 2,646 711 1,947 1,981 429 Commercial real estate—construction 242 242 72 — — — Residential mortgage 68 68 68 32 32 23 Home equity 29 49 1 — — — Total: Commercial and industrial $ 60 $ 71 $ 6 $ 127 $ 177 $ 51 Commercial real estate 4,088 5,280 711 3,901 4,001 429 Commercial real estate—construction 860 860 72 — — — Residential mortgage 1,305 1,339 68 1,761 1,466 23 Home equity 140 178 1 115 137 — * Loans acquired with credit deterioration are presented net of credit fair value adjustment. Average recorded investment of impaired loans and related interest income recognized for the years ended December 31, 2016, 2015, and 2014 are summarized as follows: December 31, 2016 December 31, 2015 December 31, 2014 (Dollars in thousands) Average Interest Average Interest Average Interest With no related allowance recorded: Commercial and industrial: Commercial and industrial $ 9 $ — $ 19 $ — $ 72 $ — Acquired with credit deterioration — — — 205 — — Commercial real estate: Commercial real estate 820 — 1,051 14 1,966 346 Acquired with credit deterioration 810 164 926 350 — — Commercial real estate—construction: Commercial real estate—construction 124 — — — — — Residential mortgage: Residential mortgage 821 21 816 8 541 — Acquired with credit deterioration 378 4 400 — — — Home equity: Home equity 75 — 107 — 29 — Acquired with credit deterioration — — — 3 — — With an allowance recorded: Commercial and industrial $ 59 $ — $ 123 $ — $ 93 $ — Commercial real estate 2,177 — 1,721 — 6,823 — Commercial real estate—construction 48 — — — — — Residential mortgage 14 — 25 — — — Home equity 32 — — — 76 — Total: Commercial and industrial $ 68 $ — $ 142 $ 205 $ 165 $ — Commercial real estate 3,807 164 3,698 364 8,789 346 Commercial real estate—construction 172 — — — — — Residential mortgage 1,213 25 1,241 8 541 — Home equity 107 — 107 3 105 — Nonaccrual loans by loan portfolio class as of December 31, 2016 and 2015 are summarized as follows: (Dollars in thousands) 2016 2015 Commercial and industrial $ 4 $ 66 Commercial real estate 2,939 2,607 Commercial real estate—construction 860 — Residential mortgage 715 1,630 Home equity 140 115 $ 4,658 $ 4,418 If nonaccrual loans and leases had been current in accordance with their original terms and had been outstanding throughout the period or since origination, if held for part of the period, Mid Penn would have recorded interest income on these loans of $666,000, $778,000, and $798,000, in the years ended December 31, 2016, 2015, and 2014, respectively. Mid Penn has no commitments to lend additional funds to borrowers with impaired or nonaccrual loans. The performance and credit quality of the loan portfolio is also monitored by the analyzing the age of the loans receivable as determined by the length of time a recorded payment is past due. The classes of the loan portfolio summarized by the past due status as of December 31, 2016 and 2015 are summarized as follows: (Dollars in thousands) December 31, 2016 30-59 60-89 Greater Total Current Total Loans Commercial and industrial: Commercial and industrial $ 164 $ 12 $ 4 $ 180 $ 172,338 $ 172,518 $ — Commercial real estate: Commercial real estate 475 — 1,004 1,479 444,203 445,682 — Acquired with credit deterioration — — 59 59 783 842 59 Commercial real estate—construction: Commercial real estate—construction — 404 84 488 53,888 54,376 — Lease financing: Lease financing — — — — 425 425 — Residential mortgage: Residential mortgage 548 124 237 909 98,159 99,068 — Acquired with credit deterioration — — 238 238 151 389 — Home equity: Home equity 33 13 125 171 37,437 37,608 — Consumer: Consumer — — — — 3,016 3,016 — Total $ 1,220 $ 553 $ 1,751 $ 3,524 $ 810,400 $ 813,924 $ 59 (Dollars in thousands) December 31, 2015 30-59 60-89 Greater Total Current Total Loans Commercial and industrial: Commercial and industrial $ 55 $ 204 $ 66 $ 325 $ 159,936 $ 160,261 $ — Commercial real estate: Commercial real estate 211 608 1,456 2,275 366,258 368,533 — Acquired with credit deterioration 215 518 55 788 143 931 55 Commercial real estate—construction: Commercial real estate—construction — — — — 68,068 68,068 — Lease financing: Lease financing — — — — 727 727 — Residential mortgage: Residential mortgage 694 550 778 2,022 98,243 100,265 — Acquired with credit deterioration 12 — 222 234 166 400 — Home equity: Home equity — 50 23 73 33,338 33,411 — Consumer: Consumer 10 5 — 15 3,902 3,917 — Total $ 1,197 $ 1,935 $ 2,600 $ 5,732 $ 730,781 $ 736,513 $ 55 Activity in the allowance for loan and lease losses for the years ended December 31, 2016, 2015, and 2014, and the recorded investment in loans receivable as of December 31, 2016, 2015, and 2014 are as follows: (Dollars in thousands) December 31, 2016 Commercial and industrial Commercial real estate Commercial real estate - construction Lease financing Residential mortgage Home equity Consumer Unallocated Total Allowance for loan and lease losses: Beginning balance $ 1,393 $ 3,552 $ 153 $ 1 $ 534 $ 317 $ 12 $ 206 $ 6,168 Charge-offs (820 ) (216 ) — — (4 ) (25 ) (42 ) — (1,107 ) Recoveries 4 211 — — 26 — 11 — 252 Provisions 1,003 776 (9 ) — (15 ) 87 22 6 1,870 Ending balance 1,580 4,323 144 1 541 379 3 212 7,183 Ending balance: individually evaluated for impairment 6 711 72 — 68 1 — — 858 Ending balance: collectively evaluated for impairment $ 1,574 $ 3,612 $ 72 $ 1 $ 473 $ 378 $ 3 $ 212 $ 6,325 Loans receivable: Ending balance $ 172,518 $ 446,524 $ 54,376 $ 425 $ 99,457 $ 37,608 $ 3,016 $ — $ 813,924 Ending balance: individually evaluated for impairment 60 3,246 860 — 916 140 — — 5,222 Ending balance: acquired with credit deterioration — 842 — — 389 — — — 1,231 Ending balance: collectively evaluated for impairment $ 172,458 $ 442,436 $ 53,516 $ 425 $ 98,152 $ 37,468 $ 3,016 $ — $ 807,471 (Dollars in thousands) December 31, 2015 Commercial Commercial Commercial real estate - Lease Residential Home Consumer Unallocated Total Allowance for loan and lease losses: Beginning balance $ 1,393 $ 3,925 $ 33 $ 2 $ 450 $ 653 $ 35 $ 225 $ 6,716 Charge-offs (130 ) (1,569 ) — — (35 ) (36 ) (14 ) — (1,784 ) Recoveries 12 75 — — 44 29 11 — 171 Provisions 118 1,121 120 (1 ) 75 (329 ) (20 ) (19 ) 1,065 Ending balance 1,393 3,552 153 1 534 317 12 206 6,168 Ending balance: individually evaluated for impairment 51 429 — — 23 — — — 503 Ending balance: collectively evaluated for impairment $ 1,342 $ 3,123 $ 153 $ 1 $ 511 $ 317 $ 12 $ 206 $ 5,665 Loans receivable: Ending balance $ 160,261 $ 369,464 $ 68,068 $ 727 $ 100,665 $ 33,411 $ 3,917 $ — $ 736,513 Ending balance: individually evaluated for impairment 127 2,970 — — 1,361 115 — — 4,573 Ending balance: acquired with credit deterioration — 931 — — 400 — — — 1,331 Ending balance: collectively evaluated for impairment $ 160,134 $ 365,563 $ 68,068 $ 727 $ 98,904 33,296 $ 3,917 $ — $ 730,609 (Dollars in thousands) December 31, 2014 Commercial and industrial Commercial real estate Commercial real estate - construction Lease financing Residential mortgage Home equity Consumer Unallocated Total Allowance for loan and lease losses: Beginning Balance $ 1,187 $ 4,006 $ 9 $ — $ 581 $ 441 $ 72 $ 21 $ 6,317 Charge-offs (62 ) (1,057 ) — — (133 ) (43 ) (33 ) — (1,328 ) Recoveries 13 13 — — 20 1 63 — 110 Provisions 255 963 24 2 (18 ) 254 (67 ) 204 1,617 Ending balance 1,393 3,925 33 2 450 653 35 225 6,716 Ending balance: individually evaluated for impairment 137 1,382 — — — 115 — — 1,634 Ending balance: collectively evaluated for impairment $ 1,256 $ 2,543 $ 33 $ 2 $ 450 $ 538 $ 35 $ 225 $ 5,082 Loans receivable: Ending balance $ 119,010 $ 297,357 $ 56,076 $ 1,121 $ 66,442 $ 28,506 $ 3,021 $ — $ 571,533 Ending balance: individually evaluated for impairment 618 8,925 — — 1,146 240 — — 10,929 Ending balance: collectively evaluated for impairment $ 118,392 $ 288,432 $ 56,076 $ 1,121 $ 65,296 $ 28,266 $ 3,021 $ — $ 560,604 The recorded investments in troubled debt restructured loans at December 31, 2016 and 2015 are as follows: Pre-Modification Post-Modification (Dollars in thousands) December 31, 2016 Outstanding Recorded Investment Outstanding Recorded Investment Recorded Investment Commercial and industrial $ 40 $ 35 $ 5 Commercial real estate 4,569 4,031 2,871 Residential mortgage 759 757 639 $ 5,368 $ 4,823 $ 3,515 Pre-Modification Post-Modification (Dollars in thousands) December 31, 2015 Outstanding Recorded Investment Outstanding Recorded Investment Recorded Investment Commercial and industrial $ 40 $ 35 $ 15 Commercial real estate 3,634 3,117 2,235 Residential mortgage 733 727 555 $ 4,407 $ 3,879 $ 2,805 At December 31, 2016, Mid Penn’s troubled debt restructured loans totaled $3,515,000, including five loans totaling $877,000 represented accruing impaired loans in compliance with the terms of the modification. Of the $877,000, four are accruing impaired residential mortgages to unrelated borrowers totaling $571,000 and the other one is an accruing impaired commercial real estate loan for $306,000. The remaining $2,638,000 of troubled debt restructured loans represent ten loans among four relationships, are nonaccrual impaired loans, and resulted in a collateral evaluation in accordance with the guidance on impaired loans. Two large relationships account for $2,170,000 of the $2,638,000 nonaccrual impaired troubled debt restructured loan total. As a result of the evaluation, a specific allocation and, subsequently, charge-offs have been taken as appropriate. As of December 31, 2016, there were no charge-offs associated with troubled debt restructured loans while under a forbearance agreement. As of December 31, 2016, there were no defaulted troubled debt restructured loans as all troubled debt restructured loans were current with respect to their associated forbearance agreements. There were also no defaults on troubled debt restructured loans within twelve months of restructure during 2016. One forbearance agreement was negotiated during 2008, eight forbearance agreements were negotiated during 2009, two were negotiated during 2013, one was negotiated during 2014, and three were negotiated during 2016. At December 31, 2015, Mid Penn’s troubled debt restructured loans totaled $2,805,000 of which four loans totaling $459,000 represented accruing impaired loans in compliance with the terms of the modification. Of the $459,000, three are accruing impaired residential mortgages to unrelated borrowers totaling $64,000 and the other one is an accruing impaired commercial real estate loan for $395,000. The remaining $2,346,000, representing nine loans among four relationships, are nonaccrual impaired loans, and resulted in a collateral evaluation in accordance with the guidance on impaired loans. One large relationship accounted for $1,370,000 of the $2,346,000 nonaccrual impaired troubled debt restructured loan total. As a result of the evaluation, a specific allocation and, subsequently, charge-offs have been taken as appropriate. As of December 31, 2015, there were no charge-offs associated with troubled debt restructured loans while under a forbearance agreement. As of December 31, 2015, there were no defaulted troubled debt restructured loans as all troubled debt restructured loans were current with respect to their associated forbearance agreements. There were also no defaults on troubled debt restructured loans within twelve months of restructure during 2015. One forbearance agreement was negotiated during 2008, nine forbearance agreements were negotiated during 2009, two were negotiated during 2013, and one was negotiated during 2014. Mid Penn entered into forbearance agreements on all loans currently classified as troubled debt restructures and all of these agreements have resulted in additional principal repayment. The terms of these forbearance agreements vary whereby principal payments have been decreased, interest rates have been reduced and/or the loan will be repaid as collateral is sold. There were three loans modified in 2016 and no loans modified in 2015 that resulted in troubled debt restructurings. The following table summarizes the loans whose terms have been modified resulting in troubled debt restructurings during the year ended December 31, 2016. (Dollars in thousands) December 31, 2016 Number Pre- Post- Recorded Commercial real estate 2 $ 934 $ 914 $ 914 Residential mortgage 1 68 68 68 3 $ 1,002 $ 982 $ 982 The following table provides activity for the accretable yield of purchased impaired loans for the year ended December 31, 2016. (Dollars in thousands) Accretable yield, January 1, 2016 $ 178 Accretable yield amortized to interest income (141 ) Reclassification from nonaccretable difference (a) 30 Accretable yield, December 31, 2016 $ 67 (a) Reclassification from non-accretable difference represents an increase to the estimated cash flows to be collected on the underlying portfolio. The Bank has granted loans to certain of its executive officers, directors, and their related interests. The aggregate amount of these loans was $17,594,000 and $10,657,000 at December 31, 2016 and 2015, respectively. During 2016, $14,479,000 of new loans and advances were extended and repayments totaled $7,542,000. None of these loans were past due, in nonaccrual status, or restructured at December 31, 2016.

Bank Premises and Equipment

Bank Premises and Equipment	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Bank Premises and Equipment	(9) Bank Premises and Equipment At December 31, 2016 and 2015, bank premises and equipment are as follows: (Dollars in thousands) 2016 2015 Land $ 2,315 $ 2,906 Buildings 9,517 10,789 Furniture, fixtures, and equipment 8,184 8,742 Leasehold improvements 1,432 1,212 Construction in progress 89 18 Total cost 21,537 23,667 Less accumulated depreciation (10,463 ) (9,674 ) Net book value of bank premises and equipment 11,074 13,993 Assets held for sale 1,894 — Total bank premises and equipment $ 12,968 $ 13,993 Depreciation expense was $1,658,000 in 2016, $1,485,000 in 2015, and $1,235,000 in 2014. As of December 31, 2016, assets held-for-sale consisted of three full service retail banking properties. These properties were transferred from land and buildings to assets held for sale due to Mid Penn’s intent to sell them during January 2017. An impairment charge of $142,000 was recorded on one of the properties at December 31, 2016 and included in other expenses on the Consolidated Statements of Income. On January 20, 2017, Mid Penn consummated the sale of the three properties for an aggregate sale price of $2,240,000, which exceeded Mid Penn’s combined carrying value by approximately $346,000. Two of the properties are being leased back by Mid Penn for a period of at least 15 years, and the respective gains on the sales of those properties will be recognized over the life of the leases. Operating Leases: As of December 31, 2016, Mid Penn was obligated to utilize certain premises under certain non-cancelable operating leases, which expire at various dates through the year ending December 31, 2035. Many of these leases contain renewal options and certain leases contain escalation clauses calling for rentals to be adjusted for increased real estate taxes and other operating expenses or proportionately adjusted for increases in consumer or other price indices. Four of Mid Penn’s operating leases are with related parties. The rental expense paid to related parties was $348,000 in 2016, $279,000 in 2015, and $54,000 in 2014. The future minimum payments to related parties are $346,000 (2017), $302,000 (2018), $304,000 (2019), $305,000 (2020), $213,000 (2021), and $2,118,000 thereafter. In 2016, Mid Penn entered into two subleasing agreements with escalation clauses to two unrelated parties. The first sublease agreement began on April 1, 2016, while the second sublease began on July 1, 2016. Both subleases end on March 31, 2021. The following summary reflects the future minimum rental payments by year under Mid Penn’s operating leases as of December 31, 2016, including a breakdown of the sublease rental income and future minimum payments owed to related parties. (Dollars in thousands) Lease Obligation Sublease Rental Income Net Rental Expense 2017 $ 1,121 $ 74 $ 1,047 2018 1,115 79 1,036 2019 1,116 81 1,035 2020 793 81 712 2021 582 20 562 thereafter 5,666 — 5,666 $ 10,393 $ 335 $ 10,058 Rental expense in connection with leases was $716,000 in 2016, $627,000 in 2015, and $151,000 in 2014.

Deposits

Deposits	12 Months Ended
	Dec. 31, 2016
Deposits [Abstract]
Deposits	(10) Deposits At December 31, 2016 and 2015, time deposits amounted to $182,595,000 and $160,849,000, respectively. Interest expense on certificates of deposit amounted to $2,156,000, $1,920,000, and $1,971,000 for the years ended December 31, 2016, 2015 and 2014, respectively. The aggregate amount of demand deposit overdrafts that were reclassified as loans were $285,000 at December 31, 2016, compared to $567,000 as of December 31, 2015. Time deposits at December 31, 2016, mature as follows: Time Deposits (Dollars in thousands) Less than $250,000 $250,000 or more Maturing in 2017 $ 64,993 $ 16,760 Maturing in 2018 35,238 5,360 Maturing in 2019 20,094 3,209 Maturing in 2020 20,997 950 Maturing in 2021 13,953 303 Maturing thereafter 738 — $ 156,013 $ 26,582 Brokered deposits included in the time deposit totals equaled $13,567,000, at December 31, 2016 and $11,168,000 at December 31, 2015. Deposits and other funds from related parties held by Mid Penn at December 31, 2016 and 2015 amounted to $19,279,000 and $17,163,000, respectively.

Short-term Borrowings

Short-term Borrowings	12 Months Ended
	Dec. 31, 2016
Short Term Borrowings Abstract
Short-term Borrowings	(11) Short-term Borrowings Short-term borrowings generally have original terms of less than a week. Mid Penn’s short-term borrowings consist of federal funds purchased. There were no short-term borrowings at December 31, 2016, and $31,596,000 with a rate of 0.40% at December 31, 2015. The Bank also has short-term borrowing capacity from the FHLB up to the Bank’s unused borrowing capacity of $404,204,000 at December 31, 2016, upon satisfaction of any stock purchase requirements of the FHLB. The Bank also has unused overnight lines of credit with correspondent banks amounting to $15,000,000 at December 31, 2016.

Long-term Debt

Long-term Debt	12 Months Ended
	Dec. 31, 2016
Maturities of Long-term Debt [Abstract]
Long-term Debt	(12) Long-term Debt The Bank is a member of the FHLB and through its membership, the Bank can access a number of credit products, which are utilized to provide liquidity. As of December 31, 2016 and 2015, the Bank had long-term At December 31, (Dollars in thousands) 2016 2015 Loans maturing in 2016 with rates ranging from 0.54% to 1.08% $ — $ 26,521 Loans maturing in 2017 at a rate of 3.03% 1,016 1,016 Loan maturing in 2019 at a rate of 1.87% 10,000 10,000 Loan maturing in 2026 at a rate of 4.80% 2,504 2,703 Loan maturing in 2027 at a rate of 6.71% 61 65 $ 13,581 $ 40,305 The aggregate principal amounts due on long-term debt subsequent to December 31, 2016 are $1,229,000 (2017), $223,000 (2018), $10,235,000 (2019), $246,000 (2020), $258,000 (2021), and $1,390,000 thereafter.

Subordinated Debt

Subordinated Debt	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Debt Disclosure [Abstract]
Subordinated Debt	(6) Subordinated Debt On December 9, 2015, Mid Penn sold $7,500,000 aggregate principal amount of Subordinated Debt (“Notes”) due 2025. The Notes are treated as Tier 2 capital for regulatory capital purposes. The Notes bear interest at a rate of 5.15% per year for the first five years and then float at the Wall Street Journal’s Prime Rate plus 0.50%, provided that the interest rate applicable to the outstanding principal balance will at no time be less than 4.0%. Interest will be payable quarterly in arrears on January 1, April 1, July 1 and October 1 of each year, beginning on January 1, 2016. The Notes will mature on December 9, 2025 and are redeemable in whole or in part, without premium or penalty, at any time on or after December 9, 2020, and prior to December 9, 2025. Additionally, Mid Penn may redeem the Notes in whole at any time, or in part from time to time, upon at least 30 days’ notice if: (i) a change or prospective change in law occurs that could prevent Mid Penn from deducting interest payable on the Notes for U.S. federal income tax purposes; (ii) an event occurs that precludes the Notes from being recognized as Tier 2 capital for regulatory capital purposes; or (iii) Mid Penn becomes required to register as an investment company under the Investment Company Act of 1940, as amended, in each case at 100% of the principal amount of the subordinated notes, plus accrued and unpaid interest thereon to but excluding the date of redemption. Holders of the Notes may not accelerate the maturity of the Notes, except upon Mid Penn’s or Mid Penn Bank’s bankruptcy, insolvency, liquidation, receivership or similar event. ASC Subtopic 835-30, Simplifying the Presentation of Debt Issuance Costs	(13) Subordinated Debt On December 9, 2015, Mid Penn sold $7,500,000 aggregate principal amount of its Notes due 2025. The Notes are treated as Tier 2 capital for regulatory capital purposes. The Notes bear interest at a rate of 5.15% per year for the first five years and then float at the Wall Street Journal’s Prime Rate plus 0.50%, provided that the interest rate applicable to the outstanding principal balance will at no times be less than 4.0%. Interest will be payable quarterly in arrears on January 1, April 1, July 1 and October 1 of each year, and began on January 1, 2016. The Notes will mature on December 9, 2025 and are redeemable in whole or in part, without premium or penalty, at any time on or after December 9, 2020, and prior to December 9, 2025. Additionally, Mid Penn may redeem the Notes in whole at any time, or in part from time to time, upon at least 30 days’ notice if: (i) a change or prospective change in law occurs that could prevent Mid Penn from deducting interest payable on the Notes for U.S. federal income tax purposes; (ii) an event occurs that precludes the Notes from being recognized as Tier 2 capital for regulatory capital purposes; or (iii) Mid Penn becomes required to register as an investment company under the Investment Company Act of 1940, as amended, in each case at 100% of the principal amount of the subordinated notes, plus accrued and unpaid interest thereon to but excluding the date of redemption. Holders of the Notes may not accelerate the maturity of the Notes, except upon Mid Penn’s or Mid Penn Bank, its principal banking subsidiary’s, bankruptcy, insolvency, liquidation, receivership or similar event. As of December 31, 2016, related parties held $1,930,000 of the Notes.

Fair Value Measurement

Fair Value Measurement	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurement	(4) Fair Value Measurement Fair value measurement and disclosure guidance defines fair value as the price that would be received to sell the asset or transfer the liability in an orderly transaction (that is, not a forced liquidation or distressed sale) between market participants at the measurement date under current market conditions. This guidance provides additional information on determining when the volume and level of activity for the asset or liability has significantly decreased. The guidance also includes information on identifying circumstances when a transaction may not be considered orderly. Fair value measurement and disclosure guidance provides a list of factors that a reporting entity should evaluate to determine whether there has been a significant decrease in the volume and level of activity for the asset or liability in relation to normal market activity for the asset or liability. When the reporting entity concludes there has been a significant decrease in the volume and level of activity for the asset or liability, further analysis of the information from that market is needed and significant adjustments to the related prices may be necessary to estimate fair value in accordance with the fair value measurement and disclosure guidance. This guidance clarifies that when there has been a significant decrease in the volume and level of activity for the asset or liability, some transactions may not be orderly. In those situations, the entity must evaluate the weight of the evidence to determine whether the transaction is orderly. The guidance provides a list of circumstances that may indicate that a transaction is not orderly. A transaction price that is not associated with an orderly transaction is given little, if any, weight when estimating fair value. Inputs to valuation techniques refer to the assumptions that market participants would use in measuring the fair value of an asset or liability. Inputs may be observable, meaning those that reflect the assumptions market participants would use in pricing the asset or liability developed based on market data obtained from independent sources, or unobservable, meaning those that reflect the reporting entity’s own belief about the assumptions market participants would use in pricing the asset or liability based upon the best information available in the circumstances. Fair value measurement and disclosure guidance establishes a fair value hierarchy for valuation inputs that gives the highest priority to quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. An asset’s or liability’s placement in the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement or disclosure. The fair value hierarchy is as follows: Level 1 Inputs Level 2 Inputs Level 3 Inputs A description of the valuation methodologies used for instruments measured at fair value, as well as the general classification of such instruments pursuant to the valuation hierarchy, is set forth below. There were no transfers of assets between fair value Level 1 and Level 2 for the six months ended June 30, 2017 and 2016. The following tables illustrate the assets measured at fair value on a recurring basis segregated by hierarchy fair value levels. Fair value measurements at June 30, 2017 (Dollars in thousands) Total carrying value at Quoted prices Significant observable Significant unobservable inputs Assets: June 30, 2017 (Level 1) (Level 2) (Level 3) Available-for-sale U.S. Treasury and U.S. government agencies $ 41,771 $ — $ 41,771 $ — Mortgage-backed U.S. government agencies 28,239 — 28,239 — State and political subdivision obligations 39,095 — 39,095 — Corporate debt securities 1,105 1,105 Equity securities 1,143 1,143 — — Total $ 111,353 $ 1,143 $ 110,210 $ — Fair value measurements at December 31, 2016 (Dollars in thousands) Total carrying value at Quoted prices Significant observable Significant unobservable inputs Assets: December 31, 2016 (Level 1) (Level 2) (Level 3) Available-for-sale U.S. Treasury and U.S. government agencies $ 47,012 $ 1,864 $ 45,148 $ — Mortgage-backed U.S. government agencies 25,619 — 25,619 — State and political subdivision obligations 58,838 — 58,838 — Corporate debt securities 1,100 — 1,100 Equity securities 1,056 1,056 — — Total $ 133,625 $ 2,920 $ 130,705 $ — Certain financial assets and financial liabilities are measured at fair value on a nonrecurring basis; that is, the instruments are not measured at fair value on an ongoing basis, but are subject to fair value adjustments in certain circumstances (for example, when there is evidence of impairment). The following tables illustrate the assets measured at fair value on a nonrecurring basis segregated by hierarchy fair value levels. Fair value measurements at June 30, 2017 (Dollars in thousands) Assets: Total Quoted prices Significant Significant Impaired Loans $ 2,061 $ — $ — $ 2,061 Foreclosed Assets Held for Sale — — — — Mortgage Servicing Rights 135 — — 135 Fair value measurements at December 31, (Dollars in thousands) Assets: Total Quoted prices Significant Significant Impaired Loans $ 2,404 $ — $ — $ 2,404 Foreclosed Assets Held for Sale 135 — — 135 Mortgage Servicing Rights 144 — — 144 The following tables present additional quantitative information about assets measured at fair value on a nonrecurring basis and for which Mid Penn has utilized Level 3 inputs to determine the fair value. (Dollars in thousands) Quantitative Information about Level 3 Fair Value Measurements June 30, 2017 Fair Value Valuation Technique Unobservable Input Range Weighted Impaired Loans $ 2,061 Appraisal of collateral (a) Appraisal adjustments (b) 26% - 43% 35% Foreclosed Assets Held for Sale — Appraisal of collateral (a), (c) Appraisal adjustments (b) 0% - 0% 0% Mortgage Servicing Rights 135 Multiple of annual service fee Estimated prepayment speed based on rate and term 210% - 400% 365% (Dollars in thousands) Quantitative Information about Level 3 Fair Value Measurements December 31, 2016 Fair Value Valuation Technique Unobservable Input Range Weighted Impaired Loans $ 2,404 Appraisal of collateral (a) Appraisal adjustments (b) 11% - 70% 30% Foreclosed Assets Held for Sale 135 Appraisal of collateral (a), (c) Appraisal adjustments (b) 26% - 31% 27% Mortgage Servicing Rights 144 Multiple of annual service fee Estimated prepayment speed based on rate and term 210% - 400% 365% (a) Fair value is generally determined through independent appraisals of the underlying collateral, which generally includes various level 3 inputs which are not observable. (b) Appraisals may be adjusted downward by management for qualitative factors such as economic conditions and estimated liquidation expenses. The range of liquidation expenses and other appraisal adjustments are presented as a percent of the appraisal. Higher downward adjustments are caused by negative changes to the collateral or conditions in the real estate market, actual offers or sales contracts received, or age of the appraisal. (c) Includes qualitative adjustments by management and estimated liquidation expenses. The following methodologies and assumptions were used to estimate the fair value of Mid Penn’s financial instruments: Cash and Cash Equivalents: The carrying value of cash and cash equivalents is considered to be a reasonable estimate of fair value. Interest-bearing Balances with other Financial Institutions: The estimate of fair value was determined by comparing the present value of quoted interest rates on like deposits with the weighted average yield and weighted average maturity of the balances. Securities Available for Sale: The fair value of securities classified as available-for-sale Held-to-Maturity The fair values of held-to-maturity Loans Held for Sale: The fair values of mortgage loans originated and intended for sale in the secondary market are carried at fair value, as determined by outstanding commitments from investors. Impaired Loans (included in “Net Loans and Leases” in the following tables): Mid Penn’s rating system assumes any loans classified as substandard and nonaccrual to be impaired, and all of these loans are considered collateral dependent; therefore, all of Mid Penn’s impaired loans, whether reporting a specific allowance allocation or not, are considered collateral dependent. It is Mid Penn’s policy to obtain updated third party valuations on all impaired loans collateralized by real estate within 30 days of the credit being classified as substandard nonaccrual. Prior to receipt of the updated real estate valuation Mid Penn will use any existing real estate valuation to determine any potential allowance for loan loss issues; however no allowance recommendation will be made until Mid Penn is in receipt of the updated valuation. In some instances Mid Penn is not holding real estate as collateral and is relying on business assets (personal property) for repayment. In these circumstances a collateral inspection is performed by Mid Penn personnel to determine an estimated value. The value is based on net book value, as provided by the financial statements, and discounted accordingly based on determinations made by management. Occasionally, Mid Penn will employ an outside service to provide a fair estimate of value based on auction sales or private sales. Management reviews the estimates of these third parties and discounts them accordingly based on management’s judgment, if deemed necessary. Mid Penn considers the estimates used in its impairment analysis to be Level 3 inputs. Mid Penn actively monitors the values of collateral on impaired loans. This monitoring may require the modification of collateral values, either in a positive or negative way, due to the passage of time or some other change in one or more valuation inputs. Collateral values for impaired loans will be reassessed by management at least every 12 months for possible revaluation by an independent third party. Loans: For variable rate loans that reprice frequently and which entail no significant changes in credit risk, carrying values approximated fair value. The fair value of other loans are estimated by calculating the present value of the cash flow difference between the current rate and the market rate, for the average maturity, discounted quarterly at the market rate. Foreclosed Assets Held for Sale: Certain assets included in foreclosed assets held for sale are carried at fair value and accordingly is presented as measured on a non-recurring Accrued Interest Receivable and Payable: The carrying amount of accrued interest receivable and payable approximates their fair values. Restricted Investment in Bank Stocks: The carrying amount of required and restricted investment in correspondent bank stock approximates fair value, and considers the limited marketability of such securities. Mortgage Servicing Rights: The fair value of servicing rights is based on the present value of estimated future cash flows on pools of mortgages stratified by rate and maturity date. Deposits: The fair value for demand deposits (e.g., interest and noninterest checking, savings, and money market deposit accounts) is, by definition, equal to the amount payable on demand at the reporting date (i.e. their carrying amounts). Fair value for fixed-rate certificates of deposit was estimated using a discounted cash flow calculation by combining all fixed-rate certificates into a pool with a weighted average yield and a weighted average maturity for the pool and comparing the pool with interest rates currently being offered on a similar maturity. Short-term Borrowings: Because of time to maturity, the estimated fair value of short-term borrowings approximates the book value. Long-term and Subordinated Debt: The estimated fair values of long-term and subordinated debt were determined using discounted cash flow analysis, based on currently available borrowing rates for similar types of borrowing arrangements. Commitments to Extend Credit and Letters of Credit: The fair value of commitments to extend credit is estimated using the fees currently charged to enter into similar agreements, taking into account market interest rates, the remaining terms and present credit worthiness of the counterparties. The fair value of guarantees and letters of credit is based on fees currently charged for similar agreements. The following table summarizes the carrying value and fair value of financial instruments at June 30, 2017 and December 31, 2016. (Dollars in thousands) June 30, 2017 December 31, 2016 Carrying Fair Carrying Fair Financial assets: Cash and cash equivalents $ 29,179 $ 29,179 $ 45,973 $ 45,973 Available-for-sale 111,353 111,353 133,625 133,625 Held-to-maturity 71,096 71,199 — — Loans held for sale 2,369 2,369 1,959 1,959 Net loans and leases 854,594 874,192 806,741 824,293 Restricted investment in bank stocks 3,985 3,985 2,443 2,443 Accrued interest receivable 3,991 3,991 3,928 3,928 Mortgage servicing rights 135 135 144 144 Financial liabilities: Deposits $ 987,468 $ 988,200 $ 935,373 $ 935,075 Short-term borrowings 21,468 21,468 — — Long-term debt 13,467 12,149 13,581 13,614 Subordinated debt 7,419 7,420 7,414 7,534 Accrued interest payable 788 788 515 515 Off-balance Commitments to extend credit $ — $ — $ — $ — Financial standby letters of credit — — — — The following tables present the carrying amount, fair value, and placement in the fair value hierarchy of Mid Penn’s financial instruments as of June 30, 2017 and December 31, 2016. Carrying values approximate fair values for cash and cash equivalents, interest-bearing time balances with other financial institutions, loans held for sale, restricted investment in bank stocks, mortgage servicing rights, accrued interest receivable and payable, and short-term borrowings. Other than cash and cash equivalents, which are considered Level 1 Inputs and mortgage servicing rights, which are Level 3 Inputs, these instruments are Level 2 Inputs. These tables exclude financial instruments for which the carrying amount approximates fair value, not previously disclosed. Fair Value Measurements (Dollars in thousands) June 30, 2017 Carrying Fair Value Quoted Prices in Significant Significant Financial instruments—assets Held-to-maturity $ 71,096 $ 71,199 $ — $ 71,199 $ — Net loans and leases 854,594 874,192 — — 874,192 Financial instruments—liabilities Deposits $ 987,468 $ 988,200 $ — $ 988,200 $ — Short-term borrowings 21,468 21,468 21,468 Long-term debt 13,467 12,149 — 12,149 — Subordinated debt 7,419 7,420 — 7,420 — Fair Value Measurements (Dollars in thousands) December 31, 2016 Carrying Fair Value Quoted Prices in Significant Significant Financial instruments—assets Net loans and leases $ 806,741 $ 824,293 $ — $ — $ 824,293 Financial instruments—liabilities Deposits $ 935,373 $ 935,075 $ — $ 935,075 $ — Long-term debt 13,581 13,614 — 13,614 — Subordinated debt $ 7,414 $ 7,534 $ 7,534	(14) Fair Value Measurement Fair value measurement and disclosure guidance defines fair value as the price that would be received to sell the asset or transfer the liability in an orderly transaction (that is, not a forced liquidation or distressed sale) between market participants at the measurement date under current market conditions. This guidance provides additional information on determining when the volume and level of activity for the asset or liability has significantly decreased. The guidance also includes information on identifying circumstances when a transaction may not be considered orderly. Fair value measurement and disclosure guidance provides a list of factors that a reporting entity should evaluate to determine whether there has been a significant decrease in the volume and level of activity for the asset or liability in relation to normal market activity for the asset or liability. When the reporting entity concludes there has been a significant decrease in the volume and level of activity for the asset or liability, further analysis of the information from that market is needed and significant adjustments to the related prices may be necessary to estimate fair value in accordance with the fair value measurement and disclosure guidance. This guidance clarifies that when there has been a significant decrease in the volume and level of activity for the asset or liability, some transactions may not be orderly. In those situations, the entity must evaluate the weight of the evidence to determine whether the transaction is orderly. The guidance provides a list of circumstances that may indicate that a transaction is not orderly. A transaction price that is not associated with an orderly transaction is given little, if any, weight when estimating fair value. Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Inputs to valuation techniques refer to the assumptions that market participants would use in pricing the asset or liability. Inputs may be observable, meaning those that reflect the assumptions market participants would use in pricing the asset or liability developed based on market data obtained from independent sources, or unobservable, meaning those that reflect the reporting entity’s own belief about the assumptions market participants would use in pricing the asset or liability based upon the best information available in the circumstances. Fair value measurement and disclosure guidance establishes a fair value hierarchy for valuation inputs that gives the highest priority to quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. The fair value hierarchy is as follows: Level 1 Inputs - Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; Level 2 Inputs - Quoted prices in markets that are not active, or inputs that are observable either directly or indirectly, for substantially the full term of the asset or liability; Level 3 Inputs - Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). A description of the valuation methodologies used for instruments measured at fair value, as well as the general classification of such instruments pursuant to the valuation hierarchy, is set forth below. There were no transfers of assets between fair value Level 1 and Level 2 for the years ended December 31, 2016 or 2015. The following tables illustrate the assets measured at fair value on a recurring basis segregated by hierarchy fair value levels: Fair value measurements at December 31, Total carrying value at Quoted prices in active markets Significant other observable inputs Significant unobservable inputs (Dollars in thousands) December 31, 2016 (Level 1) (Level 2) (Level 3) Assets: U.S. Treasury and U.S. government agencies $ 47,012 $ 1,864 $ 45,148 $ — Mortgage-backed U.S. government agencies 25,619 — 25,619 — State and political subdivision obligations 58,838 — 58,838 — Corporate debt securities 1,000 — 1,000 — Equity securities 1,156 1,056 100 — $ 133,625 $ 2,920 $ 130,705 $ — Fair value measurements at Total carrying value at Quoted prices in active markets Significant other observable inputs Significant unobservable inputs (Dollars in thousands) December 31, 2015 (Level 1) (Level 2) (Level 3) Assets: U.S. Treasury and U.S. government agencies $ 26,990 $ 1,861 $ 25,129 $ — Mortgage-backed U.S. government agencies 38,804 — 38,804 — State and political subdivision obligations 66,617 — 66,617 — Corporate debt securities 2,070 — 2,070 — Equity securities 1,240 1,240 — — $ 135,721 $ 3,101 $ 132,620 $ — Certain financial assets and financial liabilities are measured at fair value on a nonrecurring basis; that is, the instruments are not measured at fair value on an ongoing basis, but are subject to fair value adjustments in certain circumstances (for example, when there is evidence of impairment). The following tables illustrate the assets measured at fair value on a nonrecurring basis segregated by hierarchy fair value levels. Fair value measurements at December 31, (Dollars in thousands) Total carrying value at Quoted prices in active markets Significant other observable inputs Significant unobservable inputs December 31, 2016 (Level 1) (Level 2) (Level 3) Assets: Impaired Loans $ 2,404 $ — $ — $ 2,404 Foreclosed Assets Held for Sale 135 — — 135 Mortgage Servicing Rights 144 — — 144 Fair value measurements at December 31, (Dollars in thousands) Total carrying value at Quoted prices in active markets Significant other observable inputs Significant unobservable inputs December 31, 2015 (Level 1) (Level 2) (Level 3) Assets: Impaired Loans $ 2,088 $ — $ — $ 2,088 Foreclosed Assets Held for Sale 453 — — 453 Mortgage Servicing Rights 174 — — 174 The following tables present additional quantitative information about assets measured at fair value on a nonrecurring basis and for which Mid Penn has utilized Level 3 inputs to determine the fair value. Quantitative Information about Level 3 Fair Value Measurements (Dollars in thousands) December 31, 2016 Fair Value Estimate Valuation Technique Unobservable Input Range Weighted Average Impaired Loans $ 2,404 Appraisal of collateral (a) Appraisal adjustments (b) 11% -70% 30% Foreclosed Assets Held for Sale 135 Appraisal of collateral (a), (c) Appraisal adjustments (b) 26% - 31% 27% Mortgage Servicing Rights 144 Multiple of annual service fee Estimated prepayment speed based on rate and term 210% - 400% 365% Quantitative Information about Level 3 Fair Value Measurements (Dollars in thousands) December 31, 2015 Fair Value Estimate Valuation Technique Unobservable Input Range Weighted Average Impaired Loans $ 2,088 Appraisal of collateral (a) Appraisal adjustments (b) 11% - 60% 30% Foreclosed Assets Held for Sale 453 Appraisal of collateral (a), (c) Appraisal adjustments (b) 17% - 27% 26% Mortgage Servicing Rights 174 Multiple of annual service fee Estimated prepayment speed based on rate and term 210% - 400% 360% (a) Fair value is generally determined through independent appraisals of the underlying collateral, which generally includes various level 3 inputs which are not observable. (b) Appraisals may be adjusted downward by management for qualitative factors such as economic conditions and estimated liquidation expenses. The range of liquidation expenses and other appraisal adjustments are presented as a percent of the appraisal. Higher downward adjustments are caused by negative changes to the collateral or conditions in the real estate market, actual offers or sales contracts received, or age of the appraisal. (c) Includes qualitative adjustments by management and estimated liquidation expenses. The following methodologies and assumptions were used to estimate the fair value of certain assets and liabilities: Cash and Cash Equivalents: The carrying value of cash and cash equivalents is considered to be a reasonable estimate of fair value. Interest-bearing Balances with other Financial Institutions: The estimate of fair value was determined by comparing the present value of quoted interest rates on like deposits with the weighted average yield and weighted average maturity of the balances. Securities Available for sale: The fair value of securities classified as available for sale is determined by obtaining quoted market prices on nationally recognized securities exchanges (Level 1), or matrix pricing (level 2), which is a mathematical technique used widely in the industry to value debt securities without relying exclusively on quoted market prices for the specific securities but rather relying on the securities’ relationship to other benchmark quoted prices. Impaired Loans (included in “Net Loans and Leases” in the following tables): Mid Penn’s rating system assumes any loans classified as substandard nonaccrual to be impaired, and most of these loans are considered collateral dependent; therefore, most of Mid Penn’s impaired loans, whether reporting a specific allocation or not, are considered collateral dependent. It is Mid Penn’s policy to obtain updated third party valuations on all impaired loans collateralized by real estate as soon as practically possible of the credit being classified as substandard nonaccrual. Prior to receipt of the updated real estate valuation Mid Penn will use any existing real estate valuation to determine any potential allowance issues; however, no allowance recommendation will be made until Mid Penn is in receipt of the updated valuation. In some instances Mid Penn is not holding real estate as collateral and is relying on business assets (personal property) for repayment. In these circumstances a collateral inspection is performed by Mid Penn personnel to determine an estimated value. The value is based on net book value, as provided by the financial statements, and discounted accordingly based on determinations made by management. Occasionally, Mid Penn will employ an outside service to provide a fair estimate of value based on auction sales or private sales. Management reviews the estimates of these third parties and discounts them accordingly based on management’s judgment, if deemed necessary. Mid Penn considers the estimates used in its impairment analysis to be Level 3 inputs. Mid Penn actively monitors the values of collateral on impaired loans. This monitoring may require the modification of collateral values over time or changing circumstances by some factor, either positive or negative, from the original values. All collateral values will be assessed by management at least every 12 months for possible revaluation by an independent third party. Loans: For variable-rate loans that reprice frequently and which entail no significant changes in credit risk, carrying values approximated fair value. The fair value of other loans are estimated by calculating the present value of the cash flow difference between the current rate and the market rate, for the average maturity, discounted quarterly at the market rate. Foreclosed Assets Held for Sale: Assets included in foreclosed assets held for sale are carried at fair value, less costs to sell, and accordingly is presented as measured on a non-recurring basis. Values are estimated using Level 3 inputs, based on appraisals that consider the sales prices of property in the proximate vicinity. Accrued Interest Receivable and Payable: The carrying amount of accrued interest receivable and payable approximates their fair values. Restricted Investment in Bank Stocks: The carrying amount of required and restricted investment in correspondent bank stock approximates fair value, and considers the limited marketability of such securities. Mortgage Servicing Rights: The fair value of servicing rights is based on the present value of estimated future cash flows on pools of mortgages stratified by rate and maturity date. Deposits: The fair value for demand deposits (e.g., interest and noninterest checking, savings, and money market deposit accounts) is by definition, equal to the amount payable on demand at the reporting date (i.e. their carrying amounts). Fair value for fixed-rate certificates of deposit was estimated using a discounted cash flow calculation by combining all fixed-rate certificates into a pool with a weighted average yield and a weighted average maturity for the pool and comparing the pool with interest rates currently being offered on a similar maturity. Short-term Borrowings: Because of time to maturity, the estimated fair value of short-term borrowings approximates the book value. Long-term Borrowings and Subordinated Debt: The estimated fair values of long-term borrowings and subordinated debt were determined using discounted cash flow analysis, based on currently available borrowing rates for similar types of borrowing arrangements. Commitments to Extend Credit and Letters of Credit: The fair value of commitments to extend credit is estimated using the fees currently charged to enter into similar agreements, taking into account market interest rates, the remaining terms and present credit worthiness of the counterparties. The fair value of guarantees and letters of credit is based on fees currently charged for similar agreements. The following table summarizes the carrying value and fair value of financial instruments at December 31, 2016 and 2015. (Dollars in thousands) December 31, 2016 December 31, 2015 Carrying Fair Value Carrying Fair Value Financial assets: Cash and cash equivalents $ 45,973 $ 45,973 $ 13,284 $ 13,284 Interest-bearing time balances with other financial institutions — — 4,317 4,317 Available for sale investment securities 133,625 133,625 135,721 135,721 Net loans and leases 806,741 824,293 730,345 738,773 Restricted investment in bank stocks 2,443 2,443 4,266 4,266 Accrued interest receivable 3,928 3,928 3,813 3,813 Mortgage servicing rights 144 144 174 174 Financial liabilities: Deposits $ 935,373 $ 935,075 $ 777,043 $ 777,320 Short-term borrowings — — 31,596 31,596 Long-term debt 13,581 13,614 40,305 39,626 Subordinated debt 7,414 7,534 7,500 7,500 Accrued interest payable 515 515 390 390 Off-balance sheet financial instruments: Commitments to extend credit $ — $ — $ — $ — Financial standby letters of credit — — — — The following presents the carrying amount, fair value, and placement in the fair value hierarchy of Mid Penn’s financial instruments as of December 31, 2016 and 2015. Carrying values approximate fair values for cash and cash equivalents, interest-bearing time balances with other financial institutions, restricted investment in bank stocks, mortgage servicing rights, accrued interest receivable and payable, short-term borrowings, and subordinated debt. Other than cash and cash equivalents, which are considered Level 1 Inputs, these instruments are Level 2 Inputs. The following tables exclude financial instruments for which the placement in the fair value hierarchy has been disclosed elsewhere or for which the carrying amount approximates fair value. Fair Value Measurements (Dollars in thousands) December 31, 2016 Carrying Fair Value Quoted Prices in Significant Other Significant Financial instruments—assets Net loans and leases $ 806,741 $ 824,293 $ — $ — $ 824,293 Financial instruments—liabilities Deposits $ 935,373 $ 935,075 $ — $ 935,075 $ — Long-term debt 13,581 13,614 — 13,614 — Fair Value Measurements (Dollars in thousands) December 31, 2015 Carrying Fair Value Quoted Prices in Significant Other Significant (Level 3) Financial instruments—assets Net loans and leases $ 730,345 $ 738,773 $ — $ — $ 738,773 Financial instruments—liabilities Deposits $ 777,043 $ 777,320 $ — $ 777,320 $ — Long-term debt 40,305 39,626 — 39,626 —

Defined Benefit Plans

Defined Benefit Plans	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Defined Benefit Plans	(7) Defined Benefit Plans Mid Penn has an unfunded noncontributory defined benefit retirement plan for directors. The plan provides defined benefits based on years of service. In addition, Mid Penn sponsors a defined benefit health care plan that provides post-retirement medical benefits and life insurance to qualifying full-time employees. These health care and life insurance plans are noncontributory. A December 31 measurement date for the plans is used. The components of net periodic benefit costs from these defined benefit plans are as follows: Three Months Ended June 30, (Dollars in thousands) Pension Benefits Other Benefits 2017 2016 2017 2016 Service cost $ 9 $ 8 $ 1 $ 1 Interest cost 11 11 5 5 Amortization (accretion) of prior service cost 4 8 (6 ) 6 Net periodic benefit cost $ 24 $ 27 $ — $ 12 Six Months Ended June 30, (Dollars in thousands) Pension Benefits Other Benefits 2017 2016 2017 2016 Service cost $ 18 $ 17 $ 2 $ 2 Interest cost 22 23 10 11 Amortization (accretion) of prior service cost 7 25 (12 ) 91 Net periodic benefit cost $ 47 $ 65 $ — $ 104
Director's Retirement Plan [Member]
Defined Benefit Plans		(15) Postretirement Benefit Plans Mid Penn has an unfunded noncontributory defined benefit Plan for directors. The Plan provides defined benefits based on years of service. Mid Penn also has other postretirement benefit Plans covering certain full-time employees. These health care and life insurance Plans are noncontributory. The significant aspects of each Plan are as follows: (a) Health Insurance For full-time employees who retire at age 55 or later, after completion of at least 20 years of service, Mid Penn will reimburse up to $5,000 in premiums for major medical insurance for a period ending on the earlier of the date the participant obtains other employment where major medical coverage is available or the date of the participant’s death; however, in all cases payment of medical premiums by Mid Penn will not exceed five years. If the retiree becomes eligible for Medicare within the five-year period beginning on his/her retirement date, the Bank will reimburse up to $5,000 in premiums for Medicare Advantage or a similar supplemental coverage. After the five-year period has expired, all Mid Penn paid benefits cease; however, the retiree may continue coverage through the Bank at his/her own expense. This Plan was amended in 2008 to encompass only those employees that had achieved ten years of full-time continuous service to Mid Penn as of January 1, 2008. Employees hired after that date and those that had not achieved the service requirements are not eligible for the Plan. (b) Life Insurance For full-time employees who retire at age 55 or later, after completion of at least 20 years of service, Mid Penn will provide term life insurance. The amount of coverage prior to age 65 will be three times the participant’s annual salary at retirement or $50,000, whichever is less. After age 65, the life insurance coverage amount will decrease by 10% per year, subject to a minimum amount of $5,000. (c) Directors’ Retirement Plan Mid Penn has an unfunded defined benefit retirement Plan for directors with benefits based on years of service. The adoption of this Plan generated unrecognized prior service cost of $274,000, which is being amortized over the expected future years of service of active directors. The unamortized balance at December 31, 2016, was $43,000. Health and Life The following tables provide a reconciliation of the changes in the Plan’s health and life insurance benefit obligations and fair value of Plan assets for the years ended December 31, 2016 and 2015, and a statement of the funded status at December 31, 2016 and 2015. December 31, (Dollars in thousands) 2016 2015 Change in benefit obligations: Benefit obligations, January 1 $ 572 $ 861 Service cost 4 13 Interest cost 23 32 Change in experience 2 (24 ) Change in assumptions 13 (4 ) Change due to plan amendment — (244 ) Benefit payments (74 ) (62 ) Benefit obligations, December 31 $ 540 $ 572 Change in fair value of plan assets: Fair value of plan assets, January 1 $ — $ — Employer contributions 74 62 Benefit payments (74 ) (62 ) Fair value of plan assets, December 31 $ — $ — Funded status at year end $ (540 ) $ (572 ) Mid Penn has capped the benefit to future retirees under its post-retirement health benefit plan. Employees who had achieved ten years of service as of January 1, 2008 and subsequently retire after at least 20 years of service are eligible for reimbursement of major medical insurance premiums up to $5,000, if the employee has not yet reached age 65. Upon becoming eligible for Medicare, Mid Penn will reimburse up to $5,000 in premiums for Medicare Advantage or a similar supplemental coverage. The maximum reimbursement period will not exceed five years regardless of retirement age and will end upon the participant obtaining other employment where major medical coverage is available or the participant’s death. The amount recognized in the consolidated balance sheet at December 31, 2016 and 2015, is as follows: (Dollars in thousands) 2016 2015 Accrued benefit liability $ 540 $ 572 The amounts recognized in accumulated other comprehensive (loss) income consist of: December 31, (Dollars in thousands) 2016 2015 Net gain, pretax $ (31 ) $ (47 ) Net prior service cost, pretax (209 ) (244 ) The accumulated benefit obligation for health and life insurance plans was $540,000 and $572,000 at December 31, 2016 and 2015, respectively. There will be $34,898 in estimated prior service costs amortized from accumulated other comprehensive income into net periodic benefit cost during 2017. The components of net periodic postretirement (income) benefit cost for 2016, 2015 and 2014 are as follows: (Dollars in thousands) 2016 2015 2014 Service cost $ 4 $ 13 $ 13 Interest cost 23 32 38 Amortization of prior service cost (35 ) — (1 ) Net periodic postretirement (income) benefit cost $ (8 ) $ 45 $ 50 Assumptions used in the measurement of Mid Penn’s benefit obligations at December 31, 2016 and 2015 are as follows: 2016 2015 Weighted-average assumptions: Discount rate 4.00 % 4.25 % Rate of compensation increase 3.00 % 3.25 % Assumptions used in the measurement of Mid Penn’s net periodic benefit cost for the years ended December 31, 2016, 2015 and 2014 are as follows: 2016 2015 2014 Weighted-average assumptions: Discount rate 4.25 % 4.00 % 4.75 % Rate of compensation increase 3.25 % 3.00 % 3.75 % Assumed health care cost trend rates at December 31, 2016, 2015 and 2014 are as follows: 2016 2015 2014 Health care cost trend rate assumed for next year 6.00 % 5.50 % 6.50 % Rate to which the cost trend rate is assumed to decline (the ultimate trend rate) 5.50 % 5.50 % 5.50 % Year that the rate reaches the ultimate trend rate 2018 2016 2016 Assumed health care cost trend rates have a significant effect on the amounts reported for the health care Plans. At December 31, 2016, a one-percentage-point change in assumed health care cost trend rates would have the following effects: One-Percentage Point (Dollars in thousands) Increase Decrease Effect on total of service and interest cost $ — $ — Effect on accumulated postretirement benefit obligation 3 3 Mid Penn expects to contribute $73,000 to its life and health benefit Plans in 2017. The following table shows the estimated benefit payments for future periods. (Dollars in thousands) 1/1/2017 to 12/31/2017 $ 73 1/1/2018 to 12/31/2018 64 1/1/2019 to 12/31/2019 61 1/1/2020 to 12/31/2020 56 1/1/2021 to 12/31/2021 30 1/1/2022 to 12/31/2026 156 Retirement Plan The following tables provide a reconciliation of the changes in the directors’ defined benefit Plan’s benefit obligations and fair value of Plan assets for the years ended December 31, 2016 and 2015 and a statement of the status at December 31, 2016 and 2015. This Plan is unfunded. December 31, (Dollars in thousands) 2016 2015 Change in benefit obligations: Benefit obligations, January 1 $ 1,150 $ 1,186 Service cost 34 33 Interest cost 46 45 Actuarial gain (13 ) (8 ) Change in assumptions (4 ) (16 ) Benefit payments (91 ) (90 ) Benefit obligations, December 31 $ 1,122 $ 1,150 Change in fair value of plan assets: Fair value of plan assets, January 1 $ — $ — Employer contributions 91 90 Benefit payments (91 ) (90 ) Fair value of plan assets, December 31 $ — $ — Funded status at year end $ (1,122 ) $ (1,150 ) Amounts recognized in the consolidated balance sheet at December 31, 2016 and 2015 are as follows: (Dollars in thousands) 2016 2015 Accrued benefit liability $ 1,122 $ 1,150 Amounts recognized in accumulated other comprehensive income (loss) consist of: December 31, (Dollars in thousands) 2016 2015 Net prior service cost, pretax $ 43 $ 64 Net loss, pretax 60 77 The accumulated benefit obligation for the retirement Plan was $1,122,000 at December 31, 2016 and $1,150,000 at December 31, 2015. The estimated prior service costs that will be amortized from accumulated other comprehensive loss into net periodic benefit cost during 2017 is $21,525. The components of net periodic retirement cost for 2016, 2015 and 2014 are as follows: (Dollars in thousands) 2016 2015 2014 Service cost $ 34 $ 33 $ 33 Interest cost 46 45 51 Amortization of prior-service cost 22 22 22 Net periodic retirement cost $ 102 $ 100 $ 106 Assumptions used in the measurement of Mid Penn’s benefit obligations at December 31, 2016 and 2015 are as follows: 2016 2015 Weighted-average assumptions: Discount rate 4.00 % 4.25 % Change in consumer price index 2.00 % 2.25 % Assumptions used in the measurement of Mid Penn’s net periodic benefit cost for the years ended December 31, 2016, 2015 and 2014 are as follows: 2016 2015 2014 Weighted-average assumptions: Discount rate 4.25 % 4.00 % 4.75 % Change in consumer price index 2.25 % 2.25 % 2.75 % Mid Penn expects to contribute $94,000 to its retirement Plan in 2017. The following table shows the estimated benefit payments for future periods. (Dollars in thousands) 1/1/2017 to 12/31/2017 $ 94 1/1/2018 to 12/31/2018 96 1/1/2019 to 12/31/2019 96 1/1/2020 to 12/31/2020 98 1/1/2021 to 12/31/2021 108 1/1/2022 to 12/31/2026 464 The Bank is the owner and beneficiary of insurance policies on the lives of certain officers and directors, which informally fund the retirement plan obligation. The aggregate cash surrender value of these policies was $3,834,000 and $3,764,000 at December 31, 2016 and 2015, respectively.

Other Benefit Plans

Other Benefit Plans	12 Months Ended
	Dec. 31, 2016
Defined Contribution Pension And Other Postretirement Plans Disclosure Abstract
Other Benefit Plans	(16) Other Benefit Plans (a) 401(k) Plan The Bank has a 401(k) plan that covers substantially all full-time employees. The Plan allows employees to contribute a portion of their salaries and wages to the Plan. The Plan provides for the Bank to match a portion of employee-elected salary deferrals, subject to certain percentage maximums of their salaries and wages. The Bank’s contribution to the Plan was $362,000, $321,000, and $216,000 for the years ending December 31, 2016, 2015, and 2014, respectively. (b) Defined-Contribution Plan The Bank has a funded contributory defined-contribution plan covering substantially all employees. The Bank did not contribute to the Plan in 2016, 2015, or 2014. (c) Deferred Compensation Plans The Bank has an executive deferred compensation plan, which allows executive officers to defer compensation for a specified period in order to provide future retirement income. The only participant in the Plan is a former executive officer. The Bank accrued a liability for the Plan of approximately $143,000 at December 31, 2016 and $160,000 at December 31, 2015. The expense related to the Plan was $6,000 in 2016, $9,000 in 2015, and $6,000 in 2014. The Bank also has a directors’ deferred compensation plan, which allows directors to defer receipt of fees for a specified period in order to provide future retirement income. At December 31, 2016 and 2015, the Bank accrued a liability of approximately $606,000 and $523,000, respectively, for this Plan. The expense related to the Plan was $21,000 in 2016, $17,000 in 2015, and $16,000 in 2014. (d) Salary Continuation Agreement The Bank maintains a Salary Continuation Agreement (“Agreement”) for a former executive officer. The Agreement provides the former executive officer with a fixed annual benefit. The benefit is payable beginning at age 65 for a period of 15 years. At December 31, 2016 and 2015, the Bank accrued a liability of approximately $254,000 and $237,000, respectively, for the Agreement. The expense related to the Agreement was $17,000 for 2016, $16,000 for 2015, and $15,000 for 2014. The Bank is the owner and beneficiary of an insurance policy on the life of the participating former executive officer, which supports the funding of the benefit obligation. The aggregate cash surrender value of this policy was approximately $1,284,000 and $1,253,000 at December 31, 2016 and 2015, respectively. (e) Split Dollar Life Insurance Arrangements At December 31, 2016 and 2015, the Bank had Split Dollar Life Insurance arrangements with two former executives for which the aggregate collateral assignment and cash surrender values are approximately $1,801,000 and $1,806,000, respectively. Mid Penn also acquired Phoenix’s Split Dollar Life Insurance arrangements in 2015 on select employees, which had aggregate cash surrender value of $3,838,000 at December 31, 2016 and $3,749,000 at December 31, 2015. (f) Employee Stock Purchase Plan Mid Penn has an Employee Stock Purchase Plan (“ESPP”) in which all employees are eligible to participate. The Plan allows employees to use a portion of their salaries and wages to purchase common shares of Mid Penn stock at the market value of shares at the end of each calendar quarter. 2016 2015 2014 ESPP shares purchased 4,465 4,162 3,432 Average purchase price per share $ 18.520 $ 15.865 $ 15.318

Federal Income Taxes

Federal Income Taxes	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Federal Income Taxes	(17) Federal Income Taxes The following temporary differences gave rise to the net deferred tax asset at December 31, 2016 and 2015. (Dollars in thousands) 2016 2015 Deferred tax assets: Allowance for loan and lease losses $ 2,442 $ 2,097 Loan fees 82 79 Deferred compensation 906 313 Benefit plans 955 586 Unrealized loss on securities 1,504 — Nonaccrual interest — 554 Business combination adjustments 720 1,166 Other 177 170 6,786 4,965 Deferred tax liabilities: Depreciation (1,175 ) (1,074 ) Bond accretion (117 ) (111 ) Goodwill and intangibles (500 ) (472 ) Unrealized gain on securities — (806 ) Prepaid expenses (312 ) (240 ) Business combination adjustments (367 ) (428 ) Other (29 ) (13 ) (2,500 ) (3,144 ) Deferred tax asset, net $ 4,286 $ 1,821 In assessing the realizability of federal or state deferred tax assets, management considers whether it is more likely than not some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during periods in which those temporary differences become deductible. Management considers the scheduled reversal of deferred tax liabilities, projected future taxable income, and prudent, feasible and permissible as well as available tax planning strategies in making this assessment. Based on the level of historical taxable income and projections for future taxable income over the periods in which the deferred tax assets are deductible, management believes it is more likely than not that Mid Penn will realize the benefits of these deferred tax assets. The provision for income taxes consists of the following: (Dollars in thousands) 2016 2015 2014 Current expense $ 2,613 $ 647 $ 1,574 Deferred (benefit) expense (336 ) 997 (112 ) Total provision for income taxes $ 2,277 $ 1,644 $ 1,462 A reconciliation of income tax at the statutory rate of 34% to Mid Penn’s effective rate is as follows: (Dollars in thousands) 2016 2015 2014 Provision at the expected statutory rate $ 3,428 $ 2,779 $ 2,435 Effect of tax-exempt income (1,089 ) (1,105 ) (1,086 ) Effect of investment in life insurance (90 ) (91 ) (68 ) Nondeductible interest 41 37 42 Nondeductible merger and acquisition expense — 34 163 Other items (13 ) (10 ) (24 ) Provision for income taxes $ 2,277 $ 1,644 $ 1,462 Mid Penn has no unrecognized tax benefits that, if recognized, would favorably affect the effective income tax rate in future periods. Mid Penn does not expect the total amount of unrecognized tax benefits to significantly increase or decrease in the next twelve months. No amounts for interest and penalties were recorded in income tax expense in the consolidated statement of income for the years ended December 31, 2016, 2015, or 2014. There were no amounts accrued for interest and penalties at December 31, 2016 or 2015. Mid Penn and its subsidiaries are subject to U.S. federal income tax and income tax for the state of Pennsylvania. With limited exceptions, Mid Penn is no longer subject to examination by taxing authorities for years before 2013.

Regulatory Matters

Regulatory Matters	12 Months Ended
	Dec. 31, 2016
Regulatory Capital Requirements [Abstract]
Regulatory Matters	(18) Regulatory Matters Mid Penn Bancorp, Inc., is a bank holding company and, as such, chooses to maintain a well-capitalized status in its bank subsidiary. Quantitative measures established by regulation to ensure capital adequacy require Mid Penn to maintain minimum amounts and ratios (set forth below) of Tier 1 Capital to average assets and of Total Capital (as defined in the regulations) to risk-weighted assets. As of December 31, 2016 and December 31, 2015, Mid Penn met all capital adequacy requirements to which the Bank is subject, and the Bank is considered “well-capitalized”. However, future changes in regulations could increase capital requirements and may have an adverse effect on capital resources. The federal banking agencies have substantially amended the regulatory risk-based capital rules applicable to Mid Penn. The amendments implemented the Basel III regulatory capital reforms and changes required by the Dodd-Frank Act. The amended rules included new minimum risk-based capital and leverage ratios, which became effective in January 2015, with certain requirements to be phased in beginning in 2016, and refined the definition of what constitutes “capital” for purposes of calculating those ratios. The new minimum capital level requirements applicable to Mid Penn include: (i) a new common equity Tier I capital ratio of 4.5%; (ii) a Tier I capital ratio of 6.0% (increased from 4.0 %); (iii) a Total Capital ratio of 8.0% (unchanged from current rules); and (iv) a Tier I leverage ratio of 4.0% for all institutions. The amended rules also establish a “capital conservation buffer” of 2.5% above the new regulatory minimum capital ratios, and would result in the following minimum ratios: (i) a common equity Tier I capital ratio of 7.0%; (ii) a Tier I capital ratio of 8.5%; and (iii) a Total Capital ratio of 10.5%. The new capital conservation buffer requirement was phased in beginning in January 2016 at 0.625% of risk-weighted assets and will increase each year until fully implemented in January 2019. An institution will be subject to limitations on paying dividends, engaging in share repurchases, and paying discretionary bonuses if its capital level falls below the buffer amount. These limitations will establish a maximum percentage of eligible retained income that could be utilized for such actions. Certain restrictions exist regarding the ability of the Bank to transfer funds to the Corporation in the form of cash dividends, loans, or advances. The amount of dividends that may be paid in any calendar year is limited to the current year’s net profits, combined with the retained net profits of the preceding two years. At December 31, 2016, $5,311,000 of undistributed earnings of the Bank included in the consolidated shareholders’ equity was available for distribution to the Corporation as dividends without prior regulatory approval, subject to regulatory capital requirements below. Mid Penn maintained the following regulatory capital levels, leverage ratios, and risk-based capital ratios as of December 31, 2016, and December 31, 2015, as follows: Capital Adequacy Actual Minimum Capital To Be Well-Capitalized (Dollars in thousands) Amount Ratio Amount Ratio Amount Ratio Corporation As of December 31, 2016 Tier 1 Capital (to Average Assets) $ 70,431 6.8 % $ 41,595 4.0 % $ N/A N/A Common Equity Tier 1 Capital (to Risk Weighted Assets) 70,431 9.1 % 34,807 4.5 % N/A N/A Tier 1 Capital (to Risk Weighted Assets) 70,431 9.1 % 46,409 6.0 % N/A N/A Total Capital (to Risk Weighted Assets) 85,148 11.0 % 61,879 8.0 % N/A N/A Bank As of December 31, 2016 Tier 1 Capital (to Average Assets) $ 77,026 7.4 % $ 41,568 4.0 % $ 51,960 5.0 % Common Equity Tier 1 Capital (to Risk Weighted Assets) 77,026 10.0 % 34,781 4.5 % 50,239 6.5 % Tier 1 Capital (to Risk Weighted Assets) 77,026 10.0 % 46,374 6.0 % 61,832 8.0 % Total Capital (to Risk Weighted Assets) 84,329 10.9 % 61,832 8.0 % 77,291 10.0 % Corporation As of December 31, 2015 Tier 1 Capital (to Average Assets) $ 64,089 7.3 % $ 35,098 4.0 % $ N/A N/A Common Equity Tier 1 Capital (to Risk Weighted Assets) 64,089 9.1 % 31,731 4.5 % N/A N/A Tier 1 Capital (to Risk Weighted Assets) 64,089 9.1 % 42,308 6.0 % N/A N/A Total Capital (to Risk Weighted Assets) 77,852 11.0 % 56,410 8.0 % N/A N/A Bank As of December 31, 2015 Tier 1 Capital (to Average Assets) $ 70,351 7.8 % $ 36,245 4.0 % $ 45,306 5.0 % Common Equity Tier 1 Capital (to Risk Weighted Assets) 70,351 10.0 % 31,698 4.5 % 45,786 6.5 % Tier 1 Capital (to Risk Weighted Assets) 70,351 10.0 % 42,264 6.0 % 56,352 8.0 % Total Capital (to Risk Weighted Assets) 76,614 10.9 % 56,352 8.0 % 70,440 10.0 %

Concentration Risk and Off-Bala

Concentration Risk and Off-Balance Sheet Risk	12 Months Ended
	Dec. 31, 2016
Concentration Risks Types No Concentration Percentage Abstract
Concentration Risk and Off-Balance Sheet Risk	(19) Concentration of Risk and Off-Balance Sheet Risk The Bank is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers. These financial instruments include commitments to extend credit and standby letters of credit. Those instruments involve, to varying degrees, elements of credit and interest rate risk in excess of the amount recognized in the consolidated balance sheets. The Bank evaluates each customer’s creditworthiness on a case-by-case basis. The amount of collateral obtained, if deemed necessary by the Bank upon extension of credit, is based on management’s credit evaluation of the borrower. Collateral held varies but may include accounts receivable, inventory, property, plant, and equipment, and income-producing commercial properties. The Bank’s exposure to credit loss in the event of nonperformance by the other party to the financial instrument for commitments to extend credit and standby letters of credit written is represented by the contractual amount of those instruments. The Bank uses the same credit policies in making commitments and conditional obligations as it does for direct, funded loans. Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since many of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. Standby letters of credit are conditional commitments issued by the Bank to guarantee the performance of a customer to a third party. The credit risk involved in issuing letters of credit is essentially the same as that involved in extending loan facilities to customers. The term of these standby letters of credit is generally one year or less. The amount of the liability as of December 31, 2016 and 2015 for guarantees under letters of credit issued is not material. As of December 31, 2016, commitments to extend credit amounted to $201,749,000 and standby letters of credit amounted to $14,000,000. As of December 31, 2015, commitments to extend credit amounted to $157,338,000 and standby letters of credit amounted to $15,805,000. Additionally, Mid Penn has sold loans to the FHLB as part of its Mortgage Partnership Finance Program (“Program). Under the terms of the Program, there is limited recourse back to Mid Penn for loans that do not perform in accordance with the terms of the loan agreement. Each loan that is sold under the Program is “credit enhanced” such that the individual loan’s rating is raised to “BBB”, as determined by the FHLB. The Program can be terminated by either the FHLB or Mid Penn, without cause, by giving notice to the other party. The FHLB has no obligation to commit to purchase any mortgage through, or from, Mid Penn. The total balance of loans sold under the Program was $9,206,000 and $5,958,000 for the years ended December 31, 2016 and 2015. Significant concentration of credit risk may occur when obligations of parties engaged in similar activities occur and accumulate in significant amounts. In analyzing the Bank’s exposure to significant concentration of credit risk, management set a parameter of 10% or more of the Bank’s total net loans outstanding as the threshold in determining whether the obligations of the same or affiliated parties would be classified as significant concentration of credit risk. Concentrations by industry, product line, type of collateral, etc., are also considered. U.S. Treasury securities, obligations of U.S. government agencies and corporations, and any assets collateralized by the same were excluded. As of December 31, 2016, commercial real estate financing was the only similar activity that met the requirements to be classified as a significant concentration of credit risk. However, there is a geographical concentration in that most of the Bank’s business activity is with customers located in Central Pennsylvania, specifically within the Bank’s trading area made up of Cumberland, Dauphin, Lancaster, Luzerne, Northumberland, and Schuylkill Counties. The Bank’s highest concentrations of credit within the loan portfolio is in commercial real estate financing (48.8 %) as of December 31, 2016.

Contingencies

Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Contingencies	(20) Contingencies Litigation: Mid Penn is subject to lawsuits and claims arising out of its normal conduct of business. In the opinion of management, after consultation with legal counsel, the ultimate disposition of these matters is not expected to have a material adverse effect on the consolidated financial condition of Mid Penn.

Common Stock

Common Stock	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Text Block [Abstract]
Common Stock	(9) Common Stock On June 25, 2014, the 2014 Restricted Stock Plan (the “Plan”) provides awards that shall not exceed, in the aggregate, 100,000 shares of common stock. Awards under the Plan are limited to employees and directors of the Company and the Bank selected by the Compensation Committee of the Board of Directors, to advance the best interest of Mid Penn and its shareholders. Share-based compensation expense relating to restricted stock is recognized on a straight-line basis over the vesting periods of the awards and is a component of salaries and benefits expense. As of June 30, 2017, a total of 16,045 restricted shares were granted under the plan, with 2,990 of the granted shares being vested, while the remaining 13,055 granted shares remain unvested. The Plan grants and vesting resulted in $19,000 in compensation expense for the three months ended June 30, 2017, while $8,000 expense was recorded for the three months ended June 30, 2016. Compensation expense related to the Plan was $37,000 for the six months ended June 30, 2017, while it was $17,000 for the same period in 2016.	(21) Common Stock Dividend Reinvestment Plan Under Mid Penn’s amended and restated dividend reinvestment plan (“DRIP”), 330,750 of Mid Penn’s authorized but unissued common stock are reserved for issuance. The DRIP also allows for voluntary cash payments within specified limits, for the purchase of additional shares. Restricted Stock Plan On June 25, 2014, the 2014 Restricted Stock Plan was registered under which awards shall not exceed, in the aggregate, 100,000 shares of common stock. The Plan was established for employees and directors of Mid Penn and the Bank, selected by the Compensation Committee of the Board of Directors, to advance the best interest of Mid Penn and its shareholders. The Plan provides those persons who have a responsibility for its growth with additional incentives by allowing them to acquire an ownership interest in Mid Penn and thereby encouraging them to contribute to the success of the company. Share-based compensation expense relating to restricted stock is recognized on a straight-line basis over the vesting periods of the awards and is a component of salaries and benefits expense. As of December 31, 2016, 16,045 shares have been granted under the Plan. Mid Penn granted 7,540 shares in 2016, 5,475 shares in 2015, and 3,500 shares in 2014. In 2016, 470 of the granted shares were cancelled due to the exit of a plan participant. The following table presents compensation expense and related tax benefits for restricted stock awards recognized on the consolidated statement of income. (Dollars in thousands) 2016 2015 2014 Compensation expense $ 53 $ 28 $ — Tax benefit (18 ) (10 ) — Net income effect $ 35 $ 18 $ — At December 31, 2016, there was $215,000 of unrecognized compensation cost related to all non-vested share-based compensation awards. This cost is expected to be recognized through July 2020. The following table presents information regarding the non-vested restricted stock for the year ended December 31, 2016. Shares Weighted- Non-vested at January 1, 2016 8,100 $ 16.13 Vested (2,115 ) 16.10 Cancelled (470 ) 16.09 Granted 7,540 18.77 Non-vested at December 31, 2016 13,055 17.66

Preferred Stock

Preferred Stock	12 Months Ended
	Dec. 31, 2016
Class of Stock Disclosures [Abstract]
Preferred Stock	(22) Preferred Stock Series B Preferred Stock Between September 26, 2012 and January 3, 2013, Mid Penn issued, via a private placement, 5,000 shares of its 7% Non-Cumulative Non-Voting Non-Convertible Perpetual Preferred Stock, Series B Preferred Stock, resulting in total gross proceeds of $5,000,000. On December 9, 2015, Mid Penn, using a portion of the proceeds from the offering of the Notes, redeemed all of its issued and outstanding shares of Series B Preferred Stock at a price equal to $1,024.67 per share, which is equal to $1,020 per share plus an amount equal to declared but unpaid dividends on December 9, 2015, for a total redemption price of $5,123,000. Small Business Lending Fund Preferred Shares On March 1, 2015, Mid Penn assumed all of the issued and outstanding shares of Phoenix with respect to 1,750 shares of Phoenix’s preferred stock issued to the Treasury in connection with the Small Business Lending Fund and issued 1,750 shares of SBLF Preferred Shares that had a $1,000 liquidation preference per share, to the Treasury. The SBLF Preferred Shares qualified as Tier 1 Capital and had terms and conditions identical to those shares of preferred stock issued by Phoenix to the Treasury. Mid Penn paid noncumulative dividends payable quarterly on January 1, April 1, July 1, and October 1. The dividend rate was 1.00% per annum for payment dates up to January 19, 2016. On December 15, 2015, Mid Penn, using a portion of the proceeds from the offering of the Notes, redeemed all of the outstanding shares of its SBLF Preferred Shares, which were held by the Treasury for an aggregate redemption price of $1,754,000, including accrued but unpaid dividends.

Parent Company Statements

Parent Company Statements	12 Months Ended
	Dec. 31, 2016
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Parent Company Statements	(23) Parent Company Statements CONDENSED BALANCE SHEETS December 31, (Dollars in thousands) 2016 2015 ASSETS Cash and cash equivalents $ 780 $ 564 Equity investments 545 626 Investment in subsidiaries 77,029 76,334 Other assets 40 14 Total assets $ 78,394 $ 77,538 LIABILITIES AND SHAREHOLDERS’ EQUITY Subordinated debt $ 7,414 $ 7,414 Other liabilities 513 56 Shareholders’ equity 70,467 70,068 Total liabilities and shareholders’ equity $ 78,394 $ 77,538 CONDENSED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME For Years Ended December 31, (Dollars in thousands) 2016 2015 2014 Income Dividends from subsidiaries $ 2,871 $ 5,662 $ 2,325 Other income 33 19 — Total Income 2,904 5,681 2,325 Expense Other expenses (606 ) (695 ) (716 ) Total Expense (606 ) (695 ) (716 ) Income before income tax and equity in undistributed earnings (loss) of subsidiaries 2,298 4,986 1,609 Equity in undistributed earnings of subsidiaries 5,311 1,346 4,012 Income before income tax 7,609 6,332 5,621 Income tax benefit 195 196 80 Net income 7,804 6,528 5,701 Series B preferred stock dividends and redemption premium — 473 350 Series C preferred stock dividends — 17 — Net income available to common shareholders $ 7,804 $ 6,038 $ 5,351 Comprehensive income $ 3,139 $ 6,827 $ 8,086 CONDENSED STATEMENTS OF CASH FLOWS For Years Ended December 31, (Dollars in thousands) 2016 2015 2014 CASH FLOWS FROM OPERATING ACTIVITIES Net income $ 7,804 $ 6,528 $ 5,701 Equity in undistributed earnings of subsidiaries (5,311 ) (1,346 ) (4,012 ) Decrease (increase) in other assets 59 (14 ) 8 Increase (decrease) in other liabilities 457 (665 ) 292 Net cash provided by operating activities 3,009 4,503 1,989 CASH FLOWS FROM INVESTING ACTIVITIES Net cash paid for acquisition — (2,949 ) — Net cash used in investing activities — (2,949 ) — CASH FLOWS FROM FINANCING ACTIVITIES Dividends paid (2,875 ) (2,175 ) (1,925 ) Series B preferred stock redemption premium — (100 ) — Series B preferred stock redemption — (5,000 ) — Series C preferred stock redemption — (1,750 ) — Employee Stock Purchase Plan 82 66 53 Deferred financing fees paid for subordinated debt issuance — (85 ) — Subordinated debt issuance — 7,500 — Net cash used in financing activities (2,793 ) (1,544 ) (1,872 ) Net increase in cash and cash equivalents 216 10 117 Cash and cash equivalents, beginning of year 564 554 437 Cash and cash equivalents, end of year $ 780 $ 564 $ 554

Recent Accounting Pronouncement

Recent Accounting Pronouncements	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
New Accounting Pronouncement Or Change In Accounting Principle Retrospective Adjustments Abstract
Recent Accounting Pronouncements	(11) Recent Accounting Pronouncements ASU 2017-08 2017-08, Premium Amortization on Purchased Callable Debt Securities. The ASU shortens the amortization period for premiums on purchased callable debt securities to the earliest call date (i.e., yield-to-earliest The ASU applies to callable debt securities with explicit, noncontingent call features that are callable at fixed prices and on preset dates. If a security may be prepaid based upon prepayments of the underlying loans, not because the issuer exercised a date specific call option, it is excluded from the scope of the new standard. However, for instruments with contingent call features, once the contingency is resolved and the security is callable at a fixed price and preset date, the security is within the scope of the amendments. Further, it applies to all premiums on callable debt securities, regardless of how they were generated. The ASU requires companies to reset the effective yield using the payment terms of the debt security if the call option is not exercised on the earliest call date. If the security has additional future call dates, any excess of the amortized cost basis over the amount repayable by the issuer at the next call date should be amortized to the next call date. It is effective for public business entities for fiscal years beginning after December 15, 2018, including interim periods within those years. For all other entities, the amendments are effective for annual periods beginning after December 15, 2019, and interim periods within annual periods beginning after December 15, 2020. Early adoption is permitted, including adoption in an interim period. If an entity early adopts the amendments in an interim period, any adjustments should be reflected as of the beginning of the fiscal year that includes that interim period. Mid Penn has early adopted this standard, and the financial statements as of and for the three month and six month periods ended June 30, 2017, reflect the impact of premium amortization on callable debt securities to the earliest call date. The adoption of this ASU did not have a material impact on Mid Penn’s consolidated financial statements. ASU 2017-07 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost. The ASU requires that an employer disaggregate the service cost component from the other components of net benefit cost. Service cost must be presented in the same line item(s) as other employee compensation costs. These costs are generally included within income from continuing operations, but in some cases may be eligible for capitalization, if certain criteria are met. All other components of net benefit cost must be presented in the income statement separately from the service cost component and outside a subtotal of income from operations, if one is presented. These generally include interest cost, actual return on plan assets, amortization of prior service cost included in accumulated other comprehensive income, and gains or losses from changes in the value of the projected benefit obligation or plan assets. If a separate line item is used to present the other components of net benefit cost, it must be appropriately described. If a separate line item is not used, an entity must disclose the line item(s) in the income statement that includes the other components of net benefit cost. The ASU clarifies that these costs are not eligible for capitalization. The amendments are effective for public business entities for fiscal years beginning after December 15, 2017, including interim periods within those years. For other entities, the amendments are effective for annual periods beginning after December 15, 2018, and interim periods within annual periods beginning after December 15, 2019. Early adoption is permitted as of the beginning of an annual period. As disclosed in Note 7, Defined Benefit Plans ASU 2017-05 2017-05, Clarifying the Scope of Asset Derecognition Guidance and Accounting for Partial Sales of Nonfinancial Assets. The ASU was issued to clarify the scope of Subtopic 610-20 610-20 610-20, In addition, the ASU indicates an entity should identify each distinct nonfinancial asset (e.g., real estate and inventory) or in substance nonfinancial asset promised to a counterparty and derecognize each asset when a counterparty obtains control of it. Finally, the ASU adds guidance on accounting for partial sales of nonfinancial assets. It requires an entity to derecognize a distinct nonfinancial asset or distinct in substance nonfinancial asset in a partial sale transaction when two criteria are met: 1) the entity does not have (or ceases to have) a controlling financial interest in the legal entity that holds the asset in accordance with Topic 810, and 2) the entity transfers control of the asset in accordance with Topic 606. The effective date and transition requirements for the ASU are the same as the effective date and transition requirements of Topic 606, and must be applied at the same date that Topic 606 is initially applied. That is, the amendments are effective for public entities for annual reporting periods beginning after December 15, 2017, including interim periods within those periods, and for nonpublic entities for annual reporting periods beginning after December 15, 2018, and interim periods within annual reporting periods beginning after December 15, 2019. Consistent with Topic 606, early adoption is permitted but no earlier than annual reporting periods beginning after December 15, 2016 for all entities. Mid Penn has evaluated this ASU and does not anticipate the adoption to have a material impact on its consolidated financial statements since Mid Penn typically does not engage in partial sale transactions. ASU 2017-04 2017-04, Intangibles—Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment. The amendments in this ASU are required for public business entities and other entities that have goodwill reported in their financial statements and have not elected the private company alternative for the subsequent measurement of goodwill. To simplify the subsequent measurement of goodwill, the Update eliminates Step 2 from the goodwill impairment test. An entity should now perform its annual or interim goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. Additionally, an entity should consider income tax effects from any tax deductible goodwill on the carrying amount of the reporting unit when measuring the goodwill impairment loss, if applicable. The ASU eliminates the requirements for any reporting unit with a zero or negative carrying amount to perform a qualitative assessment, and if it fails that qualitative test, to perform Step 2 of the goodwill impairment test. Therefore, the same impairment assessment applies to all reporting units. An entity still has the option to perform the qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. An entity should apply the amendments in this Update on a prospective basis. A public business entity should adopt the amendments in this Update for its annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. Mid Penn plans to early adopt this ASU for its annual goodwill impairment test at the end of 2017 by comparing its fair value to its carrying value. The adoption of this ASU is not expected to have a material impact on Mid Penn’s consolidated financial statements. ASU 2016-15 2016-15, Classification of Certain Cash Receipts and Cash Payments. The ASU clarifies how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The amendments are intended to reduce diversity in practice. • Cash payments for debt prepayment or extinguishment costs will be classified in financing activities. • Upon settlement of zero-coupon • Cash paid by an acquirer that isn’t soon after a business combination for the settlement of a contingent consideration liability will be separated between financing activities and operating activities. Cash payments up to the amount of the contingent consideration liability recognized at the acquisition date will be classified in financing activities; any excess will be classified in operating activities. Cash paid soon after the business combination will be classified in investing activities. • Cash proceeds received from the settlement of insurance claims will be classified on the basis of the related insurance coverage (that is, the nature of the loss). Cash proceeds from lump-sum • Cash proceeds received from the settlement of corporate-owned life insurance (“COLI”) and BOLI policies will be classified as cash inflows from investing activities. Cash payments for premiums on COLI and BOLI may be classified as cash outflows for investing, operating, or a combination of both. • A transferor’s beneficial interest obtained in a securitization of financial assets will be disclosed as a noncash activity, and cash received from beneficial interests will be classified in investing activities. • Distributions received from equity method investees will be classified using either a cumulative earnings approach or a look- through approach as an accounting policy election. The ASU contains additional guidance clarifying when an entity should separate cash receipts and cash payments and classify them into more than one class of cash flows (including when reasonable judgment is required to estimate and allocate cash flows) versus when an entity should classify the aggregate amount into one class of cash flows on the basis of predominance. The amendments are effective for public business entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017. For all other entities, the amendments in this Update are effective for fiscal years beginning after December 15, 2018, and interim periods within fiscal years beginning after December 15, 2019. Early adoption is permitted. If an entity early adopts the amendments in an interim period, any adjustments should be reflected as of the beginning of the fiscal year that includes that interim period. An entity that elects early adoption must adopt all of the amendments in the same period. Mid Penn is currently evaluating this ASU, particularly related to cash payments for debt prepayment costs and cash proceeds received from the settlement of BOLI policies as these areas might affect Mid Penn in the future. This ASU, however, is not expected to have a material impact on Mid Penn’s operating results and consolidated financial statements because the guidance only affects the classification within the statement of cash flows. ASU 2016-13 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. The ASU requires credit losses on most financial assets measured at amortized cost and certain other instruments to be measured using an expected credit loss model (referred to as the current expected credit loss (“CECL”) model). Under this model, entities will estimate credit losses over the entire contractual term of the instrument (considering estimated prepayments, but not expected extensions or modifications unless reasonable expectation of a troubled debt restructuring exists) from the date of initial recognition of that instrument. The ASU also replaces the current accounting model for purchased credit impaired loans and debt securities. The allowance for purchased financial assets with a more-than insignificant amount of credit deterioration since origination (“PCD assets”) should be determined in a similar manner to other financial assets measured on an amortized cost basis. However, upon initial recognition, the allowance is added to the purchase price (“gross up approach”) to determine the initial amortized cost basis. The subsequent accounting for PCD financial assets is the same expected loss model described above. Further, the ASU made certain targeted amendments to the existing impairment model for available-for-sale more-likely-than-not The Update has tiered effective dates, with early adoption permitted for all entities as of the fiscal year beginning after December 15, 2018. For public business entities that are SEC filers, the amendments are effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. For all other public business entities, the amendments are effective for fiscal years beginning after December 15, 2020, including interim periods within those fiscal years. For all other entities, including not-for-profit Mid Penn is currently evaluating the details of this ASU and the impact the guidance will have on Mid Penn’s consolidated financial statements. Mid Penn expects that it is possible that the ASU will result in an increase in the allowance for credit losses resulting from the change to expected losses for the estimated life of the financial asset, including an allowance for debt securities. The amount of the increase in the allowance for credit losses resulting from the new guidance will be impacted by the portfolio composition and asset quality at the adoption date, as well as economic conditions and forecasts at the time of adoption. ASU 2016-09: 2016-09, Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting. The ASU introduces targeted amendments intended to simplify the accounting for stock compensation. Specifically, the ASU requires all excess tax benefits and tax deficiencies (including tax benefits of dividends on share-based payment awards) to be recognized as income tax expense or benefit in the income statement. The tax effects of exercised or vested awards should be treated as discrete items in the reporting period in which they occur. An entity also should recognize excess tax benefits, and assess the need for a valuation allowance, regardless of whether the benefit reduces taxes payable in the current period. That is, off balance sheet accounting for net operating losses stemming from excess tax benefits would no longer be required and instead such net operating losses would be recognized when they arise. Existing net operating losses that are currently tracked off balance sheet would be recognized, net of a valuation allowance if required, through an adjustment to opening retained earnings in the period of adoption. Entities will no longer need to maintain and track an “APIC pool.” The ASU also requires excess tax benefits to be classified along with other income tax cash flows as an operating activity in the statement of cash flows. In addition, the ASU elevates the statutory tax withholding threshold to qualify for equity classification up to the maximum statutory tax rates in the applicable jurisdiction(s). The ASU also clarifies that cash paid by an employer when directly withholding shares for tax withholding purposes should be classified as a financing activity. The ASU provides an optional accounting policy election (with limited exceptions), to be applied on an entity-wide basis, to either estimate the number of awards that are expected to vest (consistent with existing U.S. GAAP) or account for forfeitures when they occur. The amendments are effective for public business entities for annual periods beginning after December 15, 2016, and interim periods within those annual periods. Early adoption is permitted. As disclosed in Note 9, Common Stock ASU 2016-02: 2016-02, Leases. The new leases standard applies a right-of-use The new leases standard requires a lessor to classify leases as either sales-type, direct financing or operating, similar to existing U.S. GAAP. Classification depends on the same five criteria used by lessees plus certain additional factors. The subsequent accounting treatment for all three lease types is substantially equivalent to existing U.S. GAAP for sales-type leases, direct financing leases, and operating leases. However, the new standard updates certain aspects of the lessor accounting model to align it with the new lessee accounting model, as well as with the new revenue standard under Topic 606. Lessees and lessors are required to provide certain qualitative and quantitative disclosures to enable users of financial statements to assess the amount, timing, and uncertainty of cash flows arising from leases. The new leases standard addresses other considerations including identification of a lease, separating lease and non-lease The amendments are effective for public business entities for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. Specific transition requirements apply. Mid Penn occupies certain offices under non-cancelable ASU 2016-01: 2016-01, Financial Instruments-Overall (Subtopic 825-10): This ASU requires equity investments to be measured at fair value with changes in fair value recognized in net income, excluding equity investments that are consolidated or accounted for under the equity method of accounting. The ASU allows equity investments without readily determinable fair values to be measured at cost minus impairment, with a qualitative assessment required to identify impairment. The ASU also requires public companies to use exit prices to measure the fair value of financial instruments, eliminates the disclosure requirements related to measurement assumptions for the fair value of instruments measured at amortized cost, and requires separate presentation of financial assets and liabilities based on form and measurement category. In addition, for liabilities measured at fair value under the fair value option, the changes in fair value due to changes in instrument-specific credit risk should be recognized in OCI. This ASU is effective for fiscal years beginning after December 15, 2017 and interim periods within those fiscal years. As of June 30, 2017, Mid Penn held $1,171,000 of equity investments (excluding restricted investments in bank stocks). Mid Penn does not expect to make significant increases in the volume of its equity investments; therefore, the adoption of this ASU is not expected to be material to Mid Penn’s consolidated financial statements. ASU 2014-09 2014-09, Revenue from Contracts with Customers (Topic 606). The amendments in this Update establish a comprehensive revenue recognition standard for virtually all industries under U.S. GAAP, including those that previously followed industry-specific guidance such as the real estate, construction and software industries. The revenue standard’s core principle is built on the contract between a vendor and a customer for the provision of goods and services. It attempts to depict the exchange of rights and obligations between the parties in the pattern of revenue recognition based on the consideration to which the vendor is entitled. To accomplish this objective, the standard requires five basic steps: (i) identify the contract with the customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations in the contract, and (v) recognize revenue when (or as) the entity satisfies a performance obligation. In August 2015, the FASB issued ASU 2015-14, Revenue from contracts with Customers (Topic 606): Deferral of the Effective Date 2014-09 In March 2016, the FASB issued ASU 2016-08, Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations (Reporting Revenue Gross versus Net) ASU 2014-09 In April 2016, the FASB issued ASU 2016-10, Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing 2014-09 , In May 2016, the FASB issued ASU 2016-12, Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients ASU 2014-09, Mid Penn’s implementation efforts include the identification of revenue within the scope of the guidance, particularly in regards to assessing collectability. Mid Penn’s review is ongoing, and it will continue to evaluate any prospective impact as additional guidance is issued and as its internal assessment progresses.	(24) Recent Accounting Pronouncements ASU 2017-04 Intangibles – Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment The amendments in this ASU are required for public business entities and other entities that have goodwill reported in their financial statements and have not elected the private company alternative for the subsequent measurement of goodwill. To simplify the subsequent measurement of goodwill, the Update eliminates Step 2 from the goodwill impairment test. An entity should now perform its annual or interim goodwill impairment test by comparing the fair value of a reporting unit with it carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unity. Additionally, an entity should consider income tax effects from any tax deductible goodwill on the carrying amount of the reporting unit when measuring the goodwill impairment loss, if applicable. The ASU eliminates the requirements for any reporting unit with a zero or negative carrying amount to perform a qualitative assessment, and if it fails that qualitative test, to perform Step 2 of the goodwill impairment test. Therefore, the same impairment assessment applies to all reporting units. An entity still has the option to perform the qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. An entity should apply the amendments in this Update on a prospective basis. A public business entity should adopt the amendments in this Update for its annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. Mid Penn elected to early adopt this ASU as it currently complies by comparing its fair value to its carrying value. The adoption of this ASU did not have a material impact on Mid Penn’s consolidated financial statements. ASU 2016-15 Classification of Certain Cash Receipts and Cash Payments The ASU clarifies how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The amendments are intended to reduce diversity in practice. • Cash payments for debt prepayment or extinguishment costs will be classified in financing activities. • Upon settlement of zero-coupon bonds and bonds with insignificant cash coupons, the portion of the payment attributable to imputed interest will be classified as an operating activity, while the portion of the payment attributable to principal will be classified as a financing activity. • Cash paid by an acquirer that isn’t soon after a business combination for the settlement of a contingent consideration liability will be separated between financing activities and operating activities. Cash payments up to the amount of the contingent consideration liability recognized at the acquisition date will be classified in financing activities; any excess will be classified in operating activities. Cash paid soon after the business combination will be classified in investing activities. • Cash proceeds received from the settlement of insurance claims will be classified on the basis of the related insurance coverage (that is, the nature of the loss). Cash proceeds from lump-sum settlements will be classified based on the nature of each loss included in the settlement. • Cash proceeds received from the settlement of corporate-owned life insurance (“COLI”) and BOLI policies will be classified as cash inflows from investing activities. Cash payments for premiums on COLI and BOLI may be classified as cash outflows for investing, operating, or a combination of both. • A transferor’s beneficial interest obtained in a securitization of financial assets will be disclosed as a noncash activity, and cash received from beneficial interests will be classified in investing activities. • Distributions received from equity method investees will be classified using either a cumulative earnings approach or a look- through approach as an accounting policy election. The ASU contains additional guidance clarifying when an entity should separate cash receipts and cash payments and classify them into more than one class of cash flows (including when reasonable judgment is required to estimate and allocate cash flows) versus when an entity should classify the aggregate amount into one class of cash flows on the basis of predominance. The amendments are effective for public business entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2017. For all other entities, the amendments in this Update are effective for fiscal years beginning after December 15, 2018, and interim periods within fiscal years beginning after December 15, 2019. Early adoption is permitted. If an entity early adopts the amendments in an interim period, any adjustments should be reflected as of the beginning of the fiscal year that includes that interim period. An entity that elects early adoption must adopt all of the amendments in the same period. Mid Penn is currently evaluating this ASU, particularly related to cash payments for debt prepayment costs and cash proceeds received from the settlement of BOLI policies as these areas might affect Mid Penn in the future. This ASU, however, is not expected to have a material impact on Mid Penn’s consolidated financial statements because the guidance only affects the classification within the statement of cash flows, ASU 2016-13 Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments The ASU requires credit losses on most financial assets measured at amortized cost and certain other instruments to be measured using an expected credit loss model (referred to as the current expected credit loss (“CECL”) model). Under this model, entities will estimate credit losses over the entire contractual term of the instrument (considering estimated prepayments, but not expected extensions or modifications unless reasonable expectation of a troubled debt restructuring exists) from the date of initial recognition of that instrument. The ASU also replaces the current accounting model for purchased credit impaired loans and debt securities. The allowance for purchased financial assets with a more-than insignificant amount of credit deterioration since origination (“PCD assets”), should be determined in a similar manner to other financial assets measured on an amortized cost basis. However, upon initial recognition, the allowance is added to the purchase price (“gross up approach”) to determine the initial amortized cost basis. The subsequent accounting for PCD financial assets is the same expected loss model described above. Further, the ASU made certain targeted amendments to the existing impairment model for available-for-sale debt securities. For an AFS debt security for which there is neither the intent nor a more-likely-than-not requirement to sell, an entity will record credit losses as an allowance rather than a write-down of the amortized cost basis. Certain incremental disclosures are required. The Update has tiered effective dates, with early adoption permitted for all entities as of the fiscal year beginning after December 15, 2018. For public business entities that are SEC filers, the amendments are effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. For all other public business entities, the amendments are effective for fiscal years beginning after December 15, 2020, including interim periods within those fiscal years. For all other entities, including not-for-profit Mid Penn is currently evaluating the details of this ASU and the impact the guidance will have on Mid Penn’s consolidated financial statements. Mid Penn expects that it is possible that the ASU will result in an increase in the allowance for credit losses resulting from the change to expected losses for the estimated life of the financial asset, including an allowance for debt securities. The amount of the increase in the allowance for credit losses resulting from the new guidance will be impacted by the portfolio composition and asset quality at the adoption date, as well as economic conditions and forecasts at the time of adoption. ASU 2016-09: Compensation-Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting. The ASU introduces targeted amendments intended to simplify the accounting for stock compensation. Specifically, the ASU requires all excess tax benefits and tax deficiencies (including tax benefits of dividends on share-based payment awards) to be recognized as income tax expense or benefit in the income statement. The tax effects of exercised or vested awards should be treated as discrete items in the reporting period in which they occur. An entity also should recognize excess tax benefits, and assess the need for a valuation allowance, regardless of whether the benefit reduces taxes payable in the current period. That is, off balance sheet accounting for net operating losses stemming from excess tax benefits would no longer be required and instead such net operating losses would be recognized when they arise. Existing net operating losses that are currently tracked off balance sheet would be recognized, net of a valuation allowance if required, through an adjustment to opening retained earnings in the period of adoption. Entities will no longer need to maintain and track an “APIC pool.” The ASU also requires excess tax benefits to be classified along with other income tax cash flows as an operating activity in the statement of cash flows. In addition, the ASU elevates the statutory tax withholding threshold to qualify for equity classification up to the maximum statutory tax rates in the applicable jurisdiction(s). The ASU also clarifies that cash paid by an employer when directly withholding shares for tax withholding purposes should be classified as a financing activity. The ASU provides an optional accounting policy election (with limited exceptions), to be applied on an entity-wide basis, to either estimate the number of awards that are expected to vest (consistent with existing U.S. GAAP) or account for forfeitures when they occur. The amendments are effective for public business entities for annual periods beginning after December 15, 2016, and interim periods within those annual periods. Early adoption is permitted. Mid Penn currently provides share-based stock compensation to members of its Senior Management team who have a responsibility for its growth as disclosed in Note 21. Mid Penn expects the adoption of this ASU to have no material impact on its consolidated financial statements as the current. ASU 2016-07: Investments-Equity Method and Joint Ventures (Topic 323): Simplifying the Transition to the Equity Method of Accounting. The ASU requires an investor to initially apply the equity method of accounting from the date it qualifies for that method, i.e., the date the investor obtains significant influence over the operating and financial policies of an investee. It also eliminates the previous requirement to retroactively adjust the investment and record a cumulative catch up for the periods that the investment had been held, but did not qualify for the equity method of accounting. The amendments are effective for all entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2016. The amendments should be applied prospectively upon their effective date to increases in the level of ownership interest or degree of influence that result in the application of the equity method. Early adoption is permitted. Mid Penn currently does not have a material volume of equity method or joint venture investments; therefore, this ASU is not expected to have a material impact on its consolidated financial statements. ASU 2016-02: Leases. The new leases standard applies a right-of-use (“ROU”) model that requires a lessee to record, for all leases with a lease term of more than 12 months, an asset representing its right to use the underlying asset and a liability to make lease payments. For leases with a term of 12 months or less, a practical expedient is available whereby a lessee may elect, by class of underlying asset, not to recognize an ROU asset or lease liability. At inception, lessees must classify all leases as either finance or operating based on five criteria. Balance sheet recognition of finance and operating leases is similar, but the pattern of expense recognition in the income statement, as well as the effect on the statement of cash flows, differs depending on the lease classification. The new leases standard requires a lessor to classify leases as either sales-type, direct financing or operating, similar to existing U.S. GAAP. Classification depends on the same five criteria used by lessees plus certain additional factors. The subsequent accounting treatment for all three lease types is substantially equivalent to existing U.S. GAAP for sales-type leases, direct financing leases, and operating leases. However, the new standard updates certain aspects of the lessor accounting model to align it with the new lessee accounting model, as well as with the new revenue standard under Topic 606. Lessees and lessors are required to provide certain qualitative and quantitative disclosures to enable users of financial statements to assess the amount, timing, and uncertainty of cash flows arising from leases. The new leases standard addresses other considerations including identification of a lease, separating lease and non-lease components of a contract, sale and leaseback transactions, modifications, combining contracts, reassessment of the lease term, and remeasurement of lease payments. It also contains comprehensive implementation guidance with practical examples. The amendments are effective for public business entities for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. Specific transition requirements apply. Mid Penn occupies certain offices under non-cancelable operating lease agreements, which currently are not reflected in its consolidated statement of condition. Mid Penn expects to recognize lease liabilities and ROU assets associated with these lease agreements; however, the extent of the impact on Mid Penn’s consolidated financial statements is currently under evaluation. ASU 2016-01: Financial Instruments-Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities This ASU requires equity investments to be measured at fair value with changes in fair value recognized in net income, excluding equity investments that are consolidated or accounted for under the equity method of accounting. The ASU allows equity investments without readily determinable fair values to be measured at cost minus impairment, with a qualitative assessment required to identify impairment. The ASU also requires public companies to use exit prices to measure the fair value of financial instruments, eliminates the disclosure requirements related to measurement assumptions for the fair value of instruments measured at amortized cost, and requires separate presentation of financials assets and liabilities based on form and measurement category. In addition, for liabilities measured a fair value under the fair value option, the changes in fair value due to changes in instrument-specific credit risk should be recognized in OCI. This ASU is effective for fiscal years beginning after December 15, 2017 and interim periods within those fiscal years. As of December 31, 2016, Mid Penn held $2,156,000 of equity investments (excluding restricted investments in bank stocks). Mid Penn does not expect to make significant increases in the volume of its equity investments; therefore, the adoption of this ASU is not expected to be material to Mid Penn’s consolidated financial statements. ASU 2015-16: Business Combination (Topic 805): Simplifying the Accounting for Measurement-Period Adjustments) The ASU requires adjustments to provisional amounts that are identified during the measurement period to be recognized in the reporting period in which the adjustment amounts are determined. This includes any effect on earnings of changes in depreciation, amortization, or other income effects as a result of the change to the provisional amounts, calculated as if the accounting had been completed at the acquisition date. In addition, the amendments in the proposed ASU would require an entity to disclose (either on the face of the income statement or in the notes) the nature and amount of measurement-period adjustments recognized in the current period, including separately the amounts in current-period income statement line items that would have been recorded in previous reporting periods if the adjustment to the provisional amounts had been recognized as of the acquisition date. The amendments are effective for public business entities for fiscal years, and for interim periods within those fiscal years, beginning after December 15, 2015. Early adoption is permitted. The amendments in this ASU should be applied prospectively to measurement-period adjustments that occur after the effective date of this ASU. Mid Penn early adopted this guidance in 2015. The adoption of this guidance was not material to the consolidated financial statements. See Note 4 “Mergers and Acquisitions” regarding business combinations. ASU 2014-09 Revenue from Contracts with Customers (Topic 606). The amendments in this Update establish a comprehensive revenue recognition standard for virtually all industries under U.S. GAAP, including those that previously followed industry-specific guidance such as the real estate, construction and software industries. The revenue standard’s core principle is built on the contract between a vendor and a customer for the provision of goods and services. It attempts to depict the exchange of rights and obligations between the parties in the pattern of revenue recognition based on the consideration to which the vendor is entitled. To accomplish this objective, the standard requires five basic steps: (i) identify the contract with the customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations in the contract, and (v) recognize revenue when (or as) the entity satisfies a performance obligation. In August 2015, the FASB issued ASU 2015-14, Revenue from contracts with Customers (Topic 606): Deferral of the Effective Date In March 2016, the FASB issued ASU 2016-08, Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations (Reporting Revenue Gross versus Net) In April 2016, the FASB issued ASU 2016-10, Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing , In May 2016, the FASB issued ASU 2016-12, Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients ASU 2014-09, including transition requirements for all amendments, is effective for interim and annual reporting periods in fiscal years beginning after December 15, 2017. Early adoption is permitted as of the original effective date for interim and annual reporting periods in fiscal years beginning after December 15, 2016. Mid Penn’s implementation efforts include the identification of revenue within the scope of the guidance, particularly in regards to assessing collectability. Mid Penn’s review is ongoing, and it will continue to evaluate any impact as additional guidance is issued and as its internal assessment progresses. ASU 2015-03: Interest—Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs. The ASU requires that debt issuance costs be reported in the balance sheet as a direct deduction from the face amount of the related liability, consistent with the presentation of debt discounts. Prior to the amendments, debt issuance costs were presented as a deferred charge (i.e., an asset) on the balance sheet. The ASU provides examples illustrating the balance sheet presentation of notes net of their related discounts and debt issuance costs. Further, the amendments require the amortization of debt issuance costs to be reported as interest expense. Similarly, debt issuance costs and any discount or premium are considered in the aggregate when determining the effective interest rate on the debt. The amendments are effective for public business entities for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. The amendments are effective for all other entities for fiscal years beginning after December 15, 2015, and interim periods within fiscal years beginning after December 15, 2016. The amendments must be applied retrospectively. All entities have the option of adopting the new requirements as of an earlier date for financial statements that have not been previously issued. Mid Penn adopted this ASU in March of 2016. The adoption of this guidance had no material impact on Mid Penn’s consolidated financial statements.

Summary of Quarterly Consolidat

Summary of Quarterly Consolidated Financial Data	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Data [Abstract]
Summary of Quarterly Consolidated Financial Data	(25) Summary of Quarterly Consolidated Financial Data (Unaudited) The following table presents summarized quarterly financial data for 2016 and 2015. 2016 Quarter Ended (Dollars in thousands, except per share data) March 31 June 30 September 30 December 31 Interest Income $ 9,697 $ 9,859 $ 10,125 $ 10,531 Interest Expense 1,282 1,316 1,367 1,402 Net Interest Income 8,415 8,543 8,758 9,129 Provision for Loan and Lease Losses 340 395 585 550 Net Interest Income After Provision for Loan Losses 8,075 8,148 8,173 8,579 Noninterest Income 1,232 1,398 1,419 1,875 Noninterest Expense 6,982 6,931 7,165 7,740 Income Before Provision for Income Taxes 2,325 2,615 2,427 2,714 Provision for Income Taxes 520 593 526 638 Net Income Available to Common Shareholders $ 1,805 $ 2,022 $ 1,901 $ 2,076 Per Share Data: Basic Earnings Per Common Share $ 0.43 $ 0.48 $ 0.45 $ 0.49 Cash Dividends Declared 0.22 0.12 0.12 0.22 2015 Quarter Ended (Dollars in thousands, except per share data) March 31 June 30 September 30 December 31 Interest Income $ 8,158 $ 9,644 $ 9,339 $ 9,349 Interest Expense 1,120 1,158 1,150 1,179 Net Interest Income 7,038 8,486 8,189 8,170 Provision for Loan and Lease Losses 300 300 265 200 Net Interest Income After Provision for Loan Losses 6,738 8,186 7,924 7,970 Noninterest Income 949 1,093 1,085 960 Noninterest Expense 6,640 6,642 6,569 6,882 Income Before Provision for Income Taxes 1,047 2,637 2,440 2,048 Provision for Income Taxes 84 593 546 421 Net Income 963 2,044 1,894 1,627 Series B Preferred Stock Dividends and Redemption Premium 87 88 88 210 Series C Preferred Stock Dividends — 4 4 9 Net Income Available to Common Shareholders $ 876 $ 1,952 $ 1,802 $ 1,408 Per Share Data: Basic Earnings Per Common Share $ 0.23 $ 0.46 $ 0.43 $ 0.35 Cash Dividends Declared 0.10 0.10 0.12 0.12

Guarantees and Commitments

Guarantees and Commitments	6 Months Ended
	Jun. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Guarantees and Commitments	(5) Guarantees and Commitments In the normal course of business, Mid Penn makes various commitments and incurs certain contingent liabilities which are not reflected in the accompanying consolidated financial statements. The commitments include various guarantees and commitments to extend credit. Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Mid Penn evaluates each customer’s creditworthiness on a case-by-case As of June 30, 2017, Mid Penn had entered into fixed asset acquisition commitments related to (i) purchasing a commercial building in Harrisburg, PA for $2,100,000; (ii) purchasing two vacant and undeveloped lots adjacent to the commercial building for approximately $462,000; and (iii) purchasing vacant land in Halifax, PA for approximately $504,000. The commercial building and adjacent lots in Harrisburg, PA will be renovated at some future time to serve as an administrative center for the Company. The Halifax land will be the site upon which Mid Penn Bank will construct a new retail office (the Company has received all required bank regulatory approvals for this branch). The purchase of the building and lots were closed and settlement payments made in July 2017. The properties are not expected to have related construction or renovations and improvements completed until late 2017 or possibly beginning in 2018; therefore, any additional costs incurred related to these properties in 2017 are not expected to have a material impact on the 2017 financial statements.

Earnings per Common Share

Earnings per Common Share	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Earnings per Common Share	(10) Earnings per Common Share Earnings per share are computed by dividing net income by the weighted average number of common shares outstanding during each of the years presented. The following data show the amounts used in computing basic earnings per common share. The computations of basic earnings per common share follow: (Dollars in thousands, except per share data) Three Months Six Months 2017 2016 2017 2016 Net income $ 2,345 $ 2,022 $ 4,339 $ 3,827 Weighted average common shares outstanding 4,234,291 4,227,992 4,234,525 4,227,362 Basic earnings per common share $ 0.55 $ 0.48 $ 1.02 $ 0.91 Mid Penn had no dilutive instruments outstanding during the periods ended June 30, 2017 and 2016.

Agreement and Plan of Merger

Agreement and Plan of Merger	6 Months Ended
	Jun. 30, 2017
Text Block [Abstract]
Agreement and Plan of Merger	(12) Agreement and Plan of Merger On March 29, 2017, Mid Penn entered into an Agreement and Plan of Merger (the “Merger Agreement”) with The Scottdale Bank and Trust Company. The Merger Agreement provides that, upon the terms and subject to the conditions set forth therein, Scottdale will merge with and into Mid Penn Bank, with Mid Penn Bank as the surviving bank (the “ Merger If the merger is completed, Scottdale shareholders will have the right to receive for each share of Scottdale common stock they own, at their election, (i) $1,166 in cash or (ii) a fraction of a share (the “exchange ratio”) of Mid Penn common stock determined by dividing (y) $1,166 by (z) the 10 trading day per share volume-weighted average price for Mid Penn common stock ending on the date that is five business days prior to the closing of the merger (the “ Average Price Completion of the Merger is subject to a number of customary conditions, including, among others, (i) the approval of the Merger Agreement by the shareholders of both Scottdale and Mid Penn, (ii) the effectiveness of the registration statement to be filed by Mid Penn with the SEC relating to the Mid Penn common stock to be issued in the Merger, (iii) approval of the listing on The Nasdaq Stock Market of the shares of Mid Penn common stock to be issued in the Merger, (iv) the absence of any order or other legal restriction prohibiting the closing of the Merger, (v) receipt of required regulatory approvals without the imposition of any condition or requirement, excluding standard conditions that are normally imposed by the regulatory authorities in bank merger transactions, that would, in the good faith reasonable judgment of the Board of Directors of either Mid Penn or Scottdale, materially and adversely affect the business, operations, financial condition, property or assets of the combined enterprise or materially impair the value of Scottdale to Mid Penn or the value of Mid Penn to Scottdale, and (vi) Lawrence J Kiefer and Mid Penn Bank entering into a mutually acceptable employment agreement effective as of the closing. Each party’s obligations to complete the Merger is also subject to certain additional customary conditions, including: (a) subject to certain exceptions, the accuracy of the representations and warranties of the other party, (b) performance in all material respects by the other party of its obligations under the Merger Agreement, (c) not more than 15% of the outstanding shares of Scottdale common stock have properly effected their dissenters rights, (d) the absence of any material adverse effect (as such term is defined in the Merger Agreement) with respect to the other party, and (e) the receipt by each party of an opinion from its counsel to the effect that the Merger will qualify as a reorganization within the meaning of Section 368(a) of the Internal Revenue Code of 1986, as amended.

Summary of Significant Accoun38

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Use of Estimates	(a) Use of Estimates The preparation of financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates. Material estimates that are particularly susceptible to significant change relate to the determination of the allowance for loan and lease losses, the assessment of other-than-temporary impairment of investment securities, the valuation of the goodwill for impairment, and the valuation of assets acquired and liabilities assumed in business combinations.
Cash and Cash Equivalents	(b) Cash and Cash Equivalents For purposes of the consolidated statements of cash flows, cash and cash equivalents include cash on hand, balances due from banks, and federal funds sold, all of which mature within ninety days.
Investment Securities	(c) Interest-bearing Time Deposits with Other Financial Institutions Interest-bearing time deposits with other financial institutions consist of certificates of deposits in other financial institutions with maturities within one year. (d) Investment Securities Available-for-sale securities include debt and equity securities. Debt and equity securities are reported at fair value, with unrealized holding gains and losses excluded from earnings and reported, net of deferred income taxes, as a component of accumulated other comprehensive income (loss) within shareholders’ equity. Premiums and discounts on debt securities are amortized as an adjustment to interest income using the interest method. Realized gains and losses on sales of investment securities are computed on the basis of specific identification of the cost of each security. Net gains on sales of investment securities were $1,046,000 in 2016, $325,000 in 2015, and $168,000 in 2014. Mid Penn had no held-to-maturity securities in 2016 and 2015.
Loans Held for Sale	(e) Loans Held for Sale Mortgage loans originated and intended for sale in the secondary market are included in loans held for sale and are carried at fair value, as determined by outstanding commitments from investors. Gains and losses on sales of mortgage loans are included in the Consolidated Statements of Income in mortgage banking income. Mortgage banking income was $922,000 in 2016, $456,000 in 2015, and $313,000 in 2014.
Loans and Allowance for Loan and Lease Losses	(f) Loans and Allowance for Loan and Lease Losses Loans receivable that management has the intent and ability to hold for the foreseeable future or until maturity or payoff are stated at their outstanding unpaid principal balances, net of an allowance for loan losses and any deferred fees or costs. Interest income is accrued on the unpaid principal balance. Residential loans held for sale are carried at fair value and are included in loans held for sale on the balance sheet. Loan origination fees, net of certain direct origination costs, are deferred and recognized as an adjustment of the yield (interest income) of the related loans. These amounts are generally being amortized over the contractual life of the loan. Premiums and discounts on purchased loans are amortized as adjustments to interest income using the effective yield method. The loan portfolio is segmented into commercial and consumer loans. Commercial loans consist of the following classes: commercial and industrial, commercial real estate, commercial real estate-construction and lease financing. Consumer loans consist of the following classes: residential mortgage loans, home equity loans and other consumer loans. For all classes of loans, the accrual of interest is discontinued when the contractual payment of principal or interest has become 90 days or more past due or management has serious doubts about further collectability of principal or interest, even though the loan is currently performing. A loan may remain on accrual status if it is in the process of collection and is either guaranteed or well secured. When a loan is placed on nonaccrual status, unpaid interest is credited to income. Interest received on nonaccrual loans, including impaired loans, generally is either applied against principal or reported as interest income, according to management’s judgment as to the collectability of principal. Generally, loans are restored to accrual status when the obligation is brought current, has performed in accordance with the contractual terms for a reasonable period of time (generally six months) and the ultimate collectability of the total contractual principal and interest is no longer in doubt. The past due status of all classes of loans receivable is determined based on contractual due dates for loan payments. Commercial and industrial Mid Penn originates commercial and industrial loans. Most of the Bank’s commercial and industrial loans have been extended to finance local and regional businesses and include short-term loans to finance machinery and equipment purchases, inventory, and accounts receivable. Commercial loans also involve the extension of revolving credit for a combination of equipment acquisitions and working capital in expanding companies. The maximum term for loans extended on machinery and equipment is based on the projected useful life of such machinery and equipment. Generally, the maximum term on non-mortgage lines of credit is one year. The loan-to-value ratio on such loans and lines of credit generally may not exceed 80% of the value of the collateral securing the loan. The Bank’s commercial business lending policy includes credit file documentation and analysis of the borrower’s character, capacity to repay the loan, the adequacy of the borrower’s capital and collateral as well as an evaluation of conditions affecting the borrower. Analysis of the borrower’s past, present, and future cash flows is also an important aspect of the Bank’s current credit analysis. Nonetheless, such loans are believed to carry higher credit risk than other extensions of credit. Commercial and industrial loans typically are made on the basis of the borrower’s ability to make repayment from the cash flow of the borrower’s business. As a result, the availability of funds for the repayment of commercial business loans may be substantially dependent on the success of the business itself, which, in turn, is likely to be dependent upon the general economic environment. Mid Penn’s commercial and industrial loans are usually, but not always, secured by business assets and personal guarantees. However, the collateral securing the loans may depreciate over time, may be difficult to appraise, and may fluctuate in value based on the success of the business. Commercial real estate and commercial real estate—construction Commercial real estate and commercial real estate construction loans generally present a higher level of risk than loans secured by one to four family residences. This greater risk is due to several factors, including the concentration of principal in a limited number of loans and borrowers, the effect of general economic conditions on income producing properties, and the increased difficulty of evaluating and monitoring these types of loans. In addition, the repayment of loans secured by commercial real estate is typically dependent upon the successful operation of the related real estate project. If the cash flow from the project is reduced, the borrower’s ability to repay the loan may be impaired. Residential mortgage Mid Penn offers a wide array of residential mortgage loans for both permanent structures and those under construction. The Bank’s residential mortgage originations are secured primarily by properties located in its primary market and surrounding areas. Residential mortgage loans have terms up to a maximum of 30 years and with loan to value ratios up to 100% of the lesser of the appraised value of the security property or the contract price. Private mortgage insurance is generally required in an amount sufficient to reduce the Bank’s exposure to at or below the 85% loan to value level. Residential mortgage loans generally do not include prepayment penalties. In underwriting residential mortgage loans, the Bank evaluates both the borrower’s ability to make monthly payments and the value of the property securing the loan. Most properties securing real estate loans made by Mid Penn are appraised by independent fee appraisers. The Bank generally requires borrowers to obtain title insurance and fire and property insurance (including flood insurance, if necessary) in an amount not less than the amount of the loan. Real estate loans originated by the Bank generally contain a “due on sale” clause allowing the Bank to declare the unpaid principal balance due and payable upon the sale of the security property. The Bank underwrites residential mortgage loans to the standards established by the secondary mortgage market, i.e., Fannie Mae, Ginnie Mae, Freddie Mac, or Pennsylvania Housing Finance Agency standards, with the intention of selling the majority of residential mortgages originated into the secondary market. In the event that the facts and circumstances surrounding a residential mortgage application do not meet all underwriting conditions of the secondary mortgage market, the Bank will evaluate the failed conditions and evaluate the potential risk of holding the residential mortgage in the Bank’s portfolio rather than rejecting the loan request. In the event that the loan is held in the Bank’s portfolio, the interest rate on the residential mortgage typically would be increased to compensate for the added portfolio risk. Consumer, including home equity Mid Penn offers a variety of secured consumer loans, including home equity, automobile, and deposit secured loans. In addition, the Bank offers other secured and unsecured consumer loans. Most consumer loans are originated in Mid Penn’s primary market and surrounding areas. The largest component of Mid Penn’s consumer loan portfolio consists of fixed rate home equity loans and variable rate home equity lines of credit. Substantially all home equity loans and lines of credit are secured by second mortgages on principal residences. The Bank will lend amounts, which, together with all prior liens, typically may be up to 85% of the appraised value of the property securing the loan. Home equity term loans may have maximum terms up to 20 years while home equity lines of credit generally have maximum terms of five years. Consumer loan terms vary according to the type and value of collateral, length of contract and creditworthiness of the borrower. The underwriting standards employed by the Bank for consumer loans include an application, a determination of the applicant’s payment history on other debts, and an assessment of ability to meet existing obligations and payments on the proposed loan. Although creditworthiness of the applicant is a primary consideration, the underwriting process also includes a comparison of the value of the collateral, if any, in relation to the proposed loan amount. Consumer loans may entail greater credit risk than do residential mortgage loans, particularly in the case of consumer loans which are unsecured or are secured by rapidly depreciable assets, such as automobiles or recreational equipment. In such cases, any repossessed collateral for a defaulted consumer loan may not provide an adequate source of repayment of the outstanding loan balance. In addition, consumer loan collections are dependent on the borrower’s continuing financial stability, and thus are more likely to be affected by adverse personal circumstances. Furthermore, the application of various federal and state laws, including bankruptcy and insolvency laws, may limit the amount that can be recovered on such loans. Junior liens inherently have more credit risk by virtue of the fact that another financial institution may have a higher security position in the case of foreclosure liquidation of collateral to extinguish the debt. Generally, foreclosure actions could become more prevalent if the real estate market weakens and property values deteriorate. Allowance for Loan and Lease Losses The allowance for credit losses consists of the allowance for loan and lease losses and the reserve for unfunded lending commitments. The allowance for loan and lease losses represents management’s estimate of losses inherent in the loan portfolio as of the balance sheet date and is recorded as a reduction to loans. The reserve for unfunded lending commitments represents management’s estimate of losses inherent in its unfunded loan commitments and is recorded in other liabilities on the consolidated balance sheet and was $120,000 at December 31, 2016 and $94,500 at December 31, 2015. The allowance for loan and lease losses is increased by the provision for loan and lease losses, and decreased by charge-offs, net of recoveries. Loans deemed to be uncollectible are charged against the allowance for loan and lease losses, and subsequent recoveries, if any, are credited to the allowance. All, or part, of the principal balance of loans are charged off to the allowance as soon as it is determined that the repayment of all, or part, of the principal balance is highly unlikely. Non-residential consumer loans are generally charged off no later than 120 days past due on a contractual basis, earlier in the event of bankruptcy, or if there is an amount deemed uncollectible. Because all identified losses are immediately charged off, no portion of the allowance for loan and lease losses is restricted to any individual loan or groups of loans, and the entire allowance is available to absorb any and all loan losses. The allowance for credit losses is maintained at a level considered adequate to provide for losses that can be reasonably anticipated. Management performs a monthly evaluation of the adequacy of the allowance. The allowance is based on Mid Penn’s past loan loss experience, known and inherent risks in the portfolio, adverse situations that may affect the borrower’s ability to repay, the estimated value of any underlying collateral, composition of the loan portfolio, current economic conditions, and other relevant factors. This evaluation is inherently subjective as it requires material estimates that may be susceptible to significant revision as more information becomes available. The allowance consists of specific, general and unallocated components. The specific component relates to loans that are classified as impaired. For loans that are classified as impaired, an allowance is established when the DCF, collateral value, or observable market price of the impaired loan is lower than the carrying value of that loan. The general component covers pools of loans by loan class including commercial loans not considered impaired, as well as smaller balance homogeneous loans, such as residential real estate, home equity and other consumer loans. These pools of loans are evaluated for loss exposure based upon historical loss rates for each of these categories of loans, adjusted for qualitative factors. These qualitative risk factors include changes in economic conditions, fluctuations in loan quality measures, changes in collateral values, changes in the experience of the lending staff and loan review systems, changes in lending policies and procedures, including underwriting standards, changes in the mix and volume of loans originated, the effect of other external factors such as competition and legal and regulatory requirements on the level of estimated credit losses in the existing loan portfolio, and shifting industry or portfolio concentrations. Each factor is assigned a value to reflect improving, stable or declining conditions based on management’s best judgment using relevant information available at the time of the evaluation. Adjustments to the factors are supported through documentation of changes in conditions in a narrative accompanying the allowance for loan loss calculation. Mid Penn generally considers a commercial loan (consisting of commercial and industrial, commercial real estate, commercial real estate-construction, and lease financing loan classes) to be impaired when it becomes 90 days or more past due and not in the process of collection or sooner when it is probable that Mid Penn will be unable to collect all contractual principal and interest due. This methodology assumes the borrower cannot or will not continue to make additional payments. At that time the loan would generally be considered collateral dependent as the DCF method would generally indicate no operating income available for evaluating the collateral position; therefore, most impaired loans are deemed to be collateral dependent. In addition, Mid Penn’s rating system assumes any loans classified as nonaccrual, included in the substandard rating, to be impaired, and most of these loans are considered collateral dependent; therefore, most of Mid Penn’s impaired loans, whether reporting a specific allocation or not, are considered collateral dependent. Mid Penn evaluates loans for charge-off on a monthly basis. Policies that govern the recommendation for charge-off are unique to the type of loan being considered. Commercial loans rated as substandard nonaccrual or lower will first have a collateral evaluation completed in accordance with the guidance on impaired loans. Once the collateral evaluation has been completed, a specific allocation of allowance is made based upon the results of the evaluation. The remaining balance remains a nonperforming loan with the original terms and interest rate intact (not restructured). In the event the loan is unsecured, the loan would have been charged-off at the recognition of impairment. Commercial real estate loans rated as impaired will also have an initial collateral evaluation completed in accordance with the guidance on impaired loans. An updated real estate valuation is ordered and the collateral evaluation is modified to reflect any variations in value. A specific allocation of allowance is made for any anticipated collateral shortfall. The remaining balance remains a nonperforming loan with the original terms and interest rate intact (not restructured). The process of charge-off for residential mortgage loans begins upon a loan becoming delinquent for 90 days and not in the process of collection. The existing appraisal is reviewed and a lien search is obtained to determine lien position and any instances of intervening liens. A new appraisal of the property will be ordered if deemed necessary by management and a collateral evaluation is completed. The loan will then be charged down to the value indicated in the evaluation. Consumer loans (including home equity loans and other consumer loans) are recommended for charge-off after reaching delinquency of 90 days and the loan is not in the process of collection. The collateral shortfall of the consumer loan is recommended for charge-off at this point. As noted above, Mid Penn assesses a specific allocation for commercial loans and commercial real estate loans. The remaining balance remains a nonperforming loan with the original terms and interest rate intact (not restructured). In addition, Mid Penn takes a preemptive step when any commercial loan becomes classified under its internal classification system. A preliminary collateral evaluation, in accordance with the guidance on impaired loans, is prepared using the existing collateral information in the loan file. This process allows Mid Penn to review both the credit and documentation files to determine the status of the information needed to make a collateral evaluation. This collateral evaluation is preliminary but allows Mid Penn to determine if any potential collateral shortfalls exist. It is Mid Penn’s policy to obtain updated third party valuations on all impaired loans collateralized by real estate as soon as practically possible of the credit being classified as substandard nonaccrual. Prior to receipt of the updated real estate valuation Mid Penn will use any existing real estate valuation to determine any potential allowance issues; however, no allowance recommendation will be made until such time Mid Penn is in receipt of the updated valuation. The Asset Recovery department employs an electronic tracking system to monitor the receipt of and need for updated appraisals. To date, there have been no material time lapses noted with the above processes. In some instances Mid Penn is not holding real estate as collateral and is relying on business assets (personal property) for repayment. In these circumstances a collateral inspection is performed by Mid Penn personnel to determine an estimated value. The value is based on net book value, as provided by the financial statements, and discounted accordingly based on determinations made by management. Occasionally, Mid Penn will employ an outside service to provide a fair estimate of value based on auction sales or private sales. Management reviews the estimates of these third parties and discounts them accordingly based on management’s judgment, if deemed necessary. For impaired loans with no valuation allowance required, Mid Penn’s practice of obtaining independent third party market valuations on the subject property as soon as practically possible of the credit being placed on nonaccrual status sometimes indicates that the loan to value ratio is sufficient to obviate the need for a specific allocation in spite of significant deterioration in real estate values in Mid Penn’s primary market area. These circumstances are determined on a case by case analysis of the impaired loans. Mid Penn actively monitors the values of collateral on impaired loans. This monitoring may require the modification of collateral values over time or changing circumstances by some factor, either positive or negative, from the original values. All collateral values will be assessed by management at least every 12 months for possible revaluation by an independent third party. An unallocated component is maintained to cover uncertainties that could affect management’s estimate of probable losses. The unallocated component of the allowance reflects the margin of imprecision inherent in the underlying assumptions used in the methodologies for estimating specific and general losses in the portfolio. Large groups of smaller balance homogeneous loans are collectively evaluated for impairment. Accordingly, Mid Penn does not separately identify individual residential mortgage loans, home equity loans and other consumer loans for impairment disclosures, unless such loans are the subject of a troubled debt restructuring agreement. Loans whose terms are modified are classified as troubled debt restructurings if the borrowers have been granted concessions and it is deemed that those borrowers are experiencing financial difficulty. Concessions granted under a troubled debt restructuring generally involve a temporary reduction in interest rate or an extension of a loan’s stated maturity date. Nonaccrual troubled debt restructurings are restored to accrual status if principal and interest payments, under the modified terms, are current for six consecutive months after modification. Loans classified as troubled debt restructurings are designated as impaired. The allowance calculation methodology includes further segregation of loan classes into risk rating categories. The borrower’s overall financial condition, repayment sources, guarantors, and value of collateral, if appropriate, are evaluated annually for commercial loans or when credit deficiencies arise, such as delinquent loan payments. Credit quality risk ratings include regulatory classifications of special mention, substandard, doubtful, and loss. Loans criticized as special mention have potential weaknesses that deserve management’s close attention. If uncorrected, the potential weaknesses may result in deterioration of the repayment prospects. Loans classified substandard have a well-defined weakness or weaknesses that jeopardize the liquidation of the debt. They include loans that are inadequately protected by the current sound net worth and paying capacity of the obligor or of the collateral pledged, if any. Loans classified doubtful have all the weaknesses inherent in loans classified substandard with the added characteristic that collection or liquidation in full, on the basis of current conditions and facts, is highly improbable. Loans classified as a loss are considered uncollectible and are charged to the allowance for loan losses. Any loans not classified as noted above are rated pass. In addition, Federal and State regulatory agencies, as an integral part of their examination process, periodically review the Bank’s allowance for loan and lease losses and may require the Bank to recognize additions to the allowance based on their judgments about information available to them at the time of their examination, which may not be currently available to management. Based on management’s comprehensive analysis of the loan portfolio, management believes the current level of the allowance for loan losses is adequate. Acquired Loans Loans that Mid Penn acquires in connection with business combinations are recorded at fair value with no carryover of the existing related allowance for loan losses. Fair value of the loans involves estimating the amount and timing of principal and interest cash flows expected to be collected on the loans and discounting those cash flows at a market rate of interest. The excess of cash flows expected at acquisition over the estimated fair value is referred to as the accretable discount and is recognized into interest income over the remaining life of the loan. The difference between contractually required payments at acquisition and the cash flows expected to be collected at acquisition is referred to as the nonaccretable discount. These loans are accounted for under the Accounting Standard Codification (“ASC”) 310-30, Loans and Debt Securities Acquired with Deteriorated Credit Quality Loans acquired through business combinations that do meet the specific criteria of ASC 310-30 are individually evaluated each period to analyze expected cash flows. To the extent that the expected cash flows of a loan have decreased due to credit deterioration, Mid Penn establishes an allowance. Loans acquired through business combinations that do not meet the specific criteria of ASC 310-30 are accounted for under ASC 310-20. These loans are initially recorded at fair value, and include credit and interest rate marks associated with acquisition accounting adjustments. Purchase premiums or discounts are subsequently amortized as an adjustment to yield over the estimated contractual lives of the loans. There is no allowance for loan losses established at the acquisition date for acquired performing loans. An allowance for loan losses is recorded for any credit deterioration in these loans subsequent to acquisition. Acquired loans that met the criteria for impaired or nonaccrual of interest prior to the acquisition may be considered performing upon acquisition, regardless of whether the customer is contractually delinquent if Mid Penn expects to fully collect the new carrying value (i.e. fair value) of the loans. As such, Mid Penn may no longer consider the loan to be nonaccrual or nonperforming and may accrue interest on these loans, including the impact of any accretable discount. In addition, charge-offs on such loans would be first applied to the nonaccretable difference portion of the fair value adjustment.
Bank Premises and Equipment	(g) Bank Premises and Equipment Land is carried at cost. Buildings, furniture, fixtures, equipment, land improvements, and leasehold improvements are stated at cost less accumulated depreciation. Depreciation is computed by the straight-line method over the estimated useful lives of the assets. Building assets are depreciated using an estimated useful life of five to fifty years. Furniture, fixtures, and equipment are depreciated using an estimated useful life of three to ten years. Land improvements are depreciated over an estimated useful life of ten to twenty years. Leasehold improvements are depreciated using an estimated useful life that is the lesser of the remaining life of the lease or ten to thirty years. Maintenance and normal repairs are charged to expense when incurred, while major additions and improvements are capitalized. Gains and losses on disposals are reflected in current operations. Bank premises and equipment designated as held for sale are carried at the lower of cost or market value.
Restricted Investments in Bank Stocks	(h) Restricted Investments in Bank Stocks Restricted investments in bank stocks represent required investments in the common stock of correspondent banks. As a member of the FHLB and Atlantic Community Bankers Bank (“ACBB”), the Bank is required to own restricted stock investments in these correspondent banks, which is carried at cost. The total amount of these restricted stock investments was $2,443,000 December 31, 2016 and $4,266,000 at December 31, 2015. This reduction was attributed to the decline in Mid Penn’s FHLB long term advances and its shift from a short-term borrowing to a short-term selling position in 2016. Total dividends received in 2016 and 2015 totaled $135,000 and $250,000, respectively.
Foreclosed Assets Held for Sale	(i) Foreclosed Assets Held for Sale Foreclosed assets held for sale consist primarily of real estate acquired through, or in lieu of, foreclosure in settlement of debt, and are recorded at fair value less cost to sell at the date of transfer, establishing a new cost basis. Any valuation adjustments required at the date of transfer are charged to the allowance for loan losses. Subsequent to acquisition, foreclosed assets are carried at fair value less costs of disposal, based upon periodic evaluations that consider changes in market conditions and development and disposal costs. Operating results from assets acquired in satisfaction of debt, including rental income less operating costs and gains or losses on the sale of, or the periodic evaluation of foreclosed assets, are recorded in noninterest expense. As of December 31, 2016, Mid Penn had $57,000 of residential real estate held in other real estate owned. There was $426,000 in loans for which formal foreclosure proceedings were in process at December 31, 2016. As of December 31, 2015, Mid Penn had $358,000 of residential real estate held in other real estate owned. There were no loans for which formal foreclosure proceedings were in process at December 31, 2015.
Mortgage Servicing Rights	(j) Mortgage Servicing Rights Mortgage servicing rights are recognized as assets upon the sale of a mortgage loan. A portion of the cost of the loan is allocated to the servicing right based upon relative fair value. The fair value of servicing rights is based on the present value of estimated future cash flows of mortgages sold, stratified by rate and maturity date. Assumptions that are incorporated in the valuation of servicing rights include assumptions about prepayment speeds on mortgages and the cost to service loans. Servicing rights are reported in core deposit and other intangibles in the Consolidated Balance Sheets and are amortized over the estimated period of future servicing income to be received on the underlying mortgage loans. The carrying amount of mortgage servicing rights was $144,000 and $174,000 at December 31, 2016 and 2015, respectively. Amortization expense is reflected in the Consolidated Statements of Income in other income and was $30,000, $24,000, and $36,000 for the years 2016, 2015, and 2014, respectively. Servicing rights are evaluated for impairment based upon estimated fair value as compared to unamortized book value.
Investment in Limited Partnership	(k) Investment in Limited Partnership Mid Penn is a limited partner in a partnership that provides low-income housing in Enola, Pennsylvania. The carrying value of Mid Penn’s investment in the limited partnership was $321,000 at December 31, 2016 and $365,000 at December 31, 2015, net of amortization, using the straight-line method and is reported in other assets on the Consolidated Balance Sheets. Mid Penn’s maximum exposure to loss is limited to the carrying value of its investment. The partnership received $46,000 in low-income housing tax credits during 2016, 2015 and 2014.
Income Taxes	(l) Income Taxes Mid Penn accounts for income taxes in accordance with income tax accounting guidance ASC Topic 740, Income Taxes Current income tax accounting guidance results in two components of income tax expense: current and deferred. Current income tax expense reflects taxes to be paid or refunded for the current period by applying the provisions of the enacted tax law to the taxable income or excess of deductions over revenues. Mid Penn determines deferred income taxes using the liability (or balance sheet) method. Under this method, the net deferred tax asset or liability is based on the tax effects of the differences between the book and tax basis of assets and liabilities, and enacted changes in tax rates and laws are recognized in the period in which they occur. Deferred income tax expense results from changes in deferred tax assets and liabilities between periods. Deferred tax assets are reduced by a valuation allowance if, based on the weight of the evidence available, it is more likely than not that some portion or all of a deferred tax asset will not be realized. Mid Penn accounts for uncertain tax positions if it is more likely than not, based on the technical merits, that the tax position will be realized or sustained upon examination. The term more-likely-than-not means a likelihood of more than 50%; the terms examined and upon examination also include resolution of the related appeals or litigation processes, if any. A tax position that meets the more-likely-than-not recognition threshold is initially and subsequently measured as the largest amount of tax benefit that has a greater than 50% likelihood of being realized upon settlement with a taxing authority that has full knowledge of all relevant information. The determination of whether or not a tax position has met the more-likely-than-not recognition threshold considers the facts, circumstances, and information available at the reporting date and is subject to management’s judgment. Mid Penn recognizes interest and penalties on income taxes, if any, as a component of income tax expense.
Core Deposit Intangible	(m) Core Deposit Intangible Core deposit intangible is a measure of the value of consumer demand and savings deposits acquired in business combinations accounted for as purchases. The core deposit intangible is being amortized over a ten-year period using a sum of the year’s digits basis. The core deposit intangible is subject to impairment testing whenever events or changes in circumstances indicate such testing.
Goodwill	(n) Goodwill Goodwill is the excess of the purchase price over the fair value of assets acquired in connection with past business acquisitions, including the 2015 Phoenix acquisition. If certain events occur, which indicate goodwill might be impaired between annual tests, goodwill must be tested when such events occur. In making this assessment, Mid Penn considers a number of factors including operating results, business plans, economic projections, anticipated future cash flows, current market data, stock price, etc. There are inherent uncertainties related to these factors and Mid Penn’s judgment in applying them to the analysis of goodwill impairment. Changes in economic and operating conditions could result in goodwill impairment in future periods. Mid Penn did not identify any impairment on its outstanding goodwill from its most recent testing, which was performed as of December 31, 2016 using a qualitative analysis. In addition, Mid Penn did not identify any impairment in 2015 or 2014 using a qualitative and quantitative analysis, respectively, in accordance with ASC 350.
Bank Owned Life Insurance	(o) Bank Owned Life Insurance Mid Penn is the owner and beneficiary of bank-owned life insurance (“BOLI”) policies on current and former directors, as well as select Miners Bank employees, which were acquired through the Phoenix acquisition. The earnings from the BOLI policies are an asset that can be liquidated, if necessary, with associated tax costs. However, Mid Penn intends to hold these policies and, accordingly, Mid Penn has not provided deferred income taxes on the earnings from the increase in cash surrender value. Mid Penn is also party to certain Split-Dollar Life Insurance Arrangements, and in accordance with GAAP, has accrued a liability related to the postretirement benefits covered by an endorsement split-dollar life insurance arrangement, and a liability for the future death benefit.
Marketing and Advertising Costs	(p) Marketing and Advertising Costs Marketing and advertising costs are expensed as incurred.
Postretirement and Other Benefit Plans	(q) Postretirement Benefit Plans Mid Penn follows the guidance in ASC Topic 715, Compensation-Retirement Benefits (r) Other Benefit Plan A funded contributory defined-contribution plan is maintained for substantially all employees. The cost of the Mid Penn defined contribution plan is charged to current operating expenses and is funded annually.
Trust Assets and Income	(s) Trust Assets and Income Assets held by the Bank in a fiduciary or agency capacity for customers of the Trust Department are not included in the consolidated financial statements since such items are not assets of the Bank. Trust income is recognized on the cash basis, which is not materially different than if it were reported on the accrual basis.
Comprehensive Income	(t) Comprehensive Income Comprehensive income consists of net income and other comprehensive income (loss). Other comprehensive income (loss) includes changes in unrealized gains and losses on securities available for sale arising during the period and reclassification adjustments for realized gains and losses on securities available for sale included in net income. Mid Penn has an unfunded noncontributory defined benefit Plan for directors and other postretirement benefit Plans covering full-time employees. These Plans utilize assumptions and methods to calculate the fair value of Plan assets and recognizing the overfunded and underfunded status of the Plans on its consolidated balance sheet. Gains and losses, prior service costs and credits are recognized in other comprehensive income (loss), net of tax, until they are amortized, or immediately upon curtailment.
Restricted Stock	(u) Restricted Stock Mid Penn provides members of Senior Management who have a responsibility for its growth with additional incentives by allowing them to acquire an ownership interest in Mid Penn through the Restricted Stock Plan. The restricted stock is non-voting and non-participating until the granted shares vest. Once the shares vest, the recipient would have full voting rights and be entitled to any commons stock dividends.
Earnings Per Share	(v) Earnings Per Share Earnings per share are computed by dividing net income available to common shareholders by the weighted average number of common shares outstanding during each of the years presented. The following data show the amounts used in computing basic earnings per share. (Dollars in thousands, except per share data) 2016 2015 2014 Net Income $ 7,804 $ 6,528 $ 5,701 Less: Dividends on Series B preferred stock — 373 350 Redemption premium on Series B preferred stock — 100 — Dividends on Series C preferred stock — 17 — Net income available to common shareholders $ 7,804 $ 6,038 $ 5,351 Weighted average common shares outstanding 4,229,284 4,106,548 3,495,705 Basic earnings per common share $ 1.85 $ 1.47 $ 1.53 Mid Penn had no dilutive instruments outstanding during the periods ended December 31, 2016, 2015, and 2014.

Summary of Significant Accoun39

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Basic Earnings (Loss) Per Share	The following data show the amounts used in computing basic earnings per share. (Dollars in thousands, except per share data) 2016 2015 2014 Net Income $ 7,804 $ 6,528 $ 5,701 Less: Dividends on Series B preferred stock — 373 350 Redemption premium on Series B preferred stock — 100 — Dividends on Series C preferred stock — 17 — Net income available to common shareholders $ 7,804 $ 6,038 $ 5,351 Weighted average common shares outstanding 4,229,284 4,106,548 3,495,705 Basic earnings per common share $ 1.85 $ 1.47 $ 1.53

Mergers and Acquisitions (Table

Mergers and Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2016
Business Combinations [Abstract]
Allocation of the Purchase Price	The allocation of the purchase price is as follows: (Dollars in thousands) Assets acquired: Cash and cash equivalents $ 11,044 Investment securities 11,331 Loans 110,363 Goodwill 2,902 Core deposit and other intangibles 578 Other assets 7,489 Total assets acquired 143,707 Liabilities assumed: Deposits 123,238 FHLB borrowings 3,570 Other liabilities 908 Total liabilities assumed 127,716 Equity acquired: Preferred stock 1,750 Total equity acquired and liabilities assumed 129,466 Consideration paid $ 14,241 Cash paid $ 2,949 Fair value of common stock issued, including replacement equity awards 11,292
Summary of the Estimated Fair Value of the Assets Acquired and Liabilities and Equity Assumed	The following table summarizes the estimated fair value of the assets acquired and liabilities and equity assumed. (Dollars in thousands) Total purchase price $ 14,241 Net assets acquired: Cash and cash equivalents 11,044 Investment securities 11,331 Restricted stock 509 Loans 110,363 Bank owned life insurance 3,673 Premises and equipment 1,792 Deferred income taxes 503 Accrued interest receivable 388 Core deposit and other intangibles 578 Other assets 624 Deposits (123,238 ) FHLB borrowings (3,570 ) Accrued interest payable (32 ) Other liabilities (876 ) Preferred stock (1,750 ) 11,339 Goodwill $ 2,902
Fair Value Adjustments Made to the Amortized Cost Basis, Presented at the Fair Value of Loans Acquired	The fair value of the financial assets acquired included loans receivable with a gross amortized cost basis of $112,816,000. The table below illustrates the fair value adjustments made to the amortized cost basis in order to present a fair value of the loans acquired. (Dollars in thousands) Gross amortized cost basis at March 1, 2015 $ 112,816 Market rate adjustment 270 Credit fair value adjustment on pools of homogeneous loans (1,461 ) Credit fair value adjustment on impaired loans (1,262 ) Fair value of purchased loans at March 1, 2015 $ 110,363
Fair Value of the Loans Acquired	The information about the acquired Phoenix loans accounted for under ASC 310-30 as of March 1, 2015 is as follows: (Dollars in thousands) Contractually required principal and interest at acquisition $ 3,548 Contractual cash flows not expected to be collected (nonaccretable discount) (804 ) Expected cash flows at acquisition 2,744 Interest component of expected cash flows (accretable discount) (458 ) Fair value of acquired loans $ 2,286
Unaudited Pro Forma Information	The following table presents unaudited pro forma information as if the merger between Mid Penn and Phoenix had been completed on January 1, 2014. The pro forma information does not necessarily reflect the results of operations that would have occurred had Mid Penn merged with Phoenix at the beginning of 2014. Supplemental pro forma earnings for 2015 were adjusted to exclude $762,000 of merger related costs incurred for the year ended December 31, 2015; the results for the year ended December 31, 2014 were adjusted to include these charges. The pro forma financial information does not include the impact of possible business model changes, nor does it consider any potential impacts of current market conditions or revenues, expense efficiencies, or other factors. The pro forma data is intended for informational purposes and is not indicative of the future results of operations. (Unaudited) Years Ended (Dollars in thousands, except per share data) 2015 2014 Net interest income after loan loss provision $ 31,454 $ 29,745 Noninterest income 4,152 4,131 Noninterest expense 27,817 26,846 Net income available to common shareholders 5,811 5,259 Net income per common share 1.38 1.25

Accumulated Other Comprehensi41

Accumulated Other Comprehensive (Loss) Income (Tables)	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive (Loss) Income, Net of Taxes	The components of accumulated other comprehensive loss, net of taxes, are as follows: (Dollars in thousands) Unrealized Defined Accumulated Other Balance—June 30, 2017 $ (1,073 ) $ 62 $ (1,011 ) Balance—December 31, 2016 $ (2,919 ) $ 66 $ (2,853 )	The components of accumulated other comprehensive (loss) income, net of taxes, are as follows: (Dollars in thousands) Unrealized (Loss) Securities Defined Benefit Plan Liability Accumulated Other Comprehensive (Loss) Income Balance—December 31, 2016 $ (2,919 ) $ 66 $ (2,853 ) Balance—December 31, 2015 $ 1,565 $ 247 $ 1,812

Investment Securities (Tables)

Investment Securities (Tables)	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Securities Financing Transactions Disclosures Abstract
Unrealized Gain (Loss) on Investments	The amortized cost, fair value, and unrealized gains and losses on investment securities at June 30, 2017 and December 31, 2016 are as follows: (Dollars in thousands) Amortized Unrealized Unrealized Fair Value June 30, 2017 Available-for-sale U.S. Treasury and U.S. government agencies $ 42,629 $ — $ 858 $ 41,771 Mortgage-backed U.S. government agencies 28,543 3 307 28,239 State and political subdivision obligations 39,539 70 514 39,095 Corporate debt securities 1,100 5 — 1,105 Equity securities 1,168 15 40 1,143 Total available-for-sale 112,979 93 1,719 111,353 Held-to-maturity U.S. Treasury and U.S. government agencies 10,984 24 5 11,003 Mortgage-backed U.S. government agencies 51,248 72 99 51,221 State and political subdivision obligations 8,864 120 9 8,975 Corporate debt securities — — — — Equity securities — — — — Total held-to-maturity 71,096 216 113 71,199 Total $ 184,075 $ 309 $ 1,832 $ 182,552 (Dollars in thousands) Amortized Unrealized Unrealized Fair Value December 31, 2016 Available-for-sale U.S. Treasury and U.S. government agencies $ 48,520 $ 34 $ 1,542 $ 47,012 Mortgage-backed U.S. government agencies 26,181 17 579 25,619 State and political subdivision obligations 61,079 91 2,332 58,838 Corporate debt securities 1,100 — — 1,100 Equity securities 1,168 — 112 1,056 Total available-for-sale $ 138,048 $ 142 $ 4,565 $ 133,625	At December 31, 2016 and 2015, amortized cost, fair value, and unrealized gains and losses on investment securities are as follows: (Dollars in thousands) Amortized Unrealized Unrealized Fair December 31, 2016 Available for sale securities: U.S. Treasury and U.S. government agencies $ 48,520 $ 34 $ 1,542 $ 47,012 Mortgage-backed U.S. government agencies 26,181 17 579 25,619 State and political subdivision obligations 61,079 91 2,332 58,838 Corporate debt securities 1,000 — — 1,000 Equity securities 1,268 — 112 1,156 $ 138,048 $ 142 $ 4,565 $ 133,625 (Dollars in thousands) Amortized Unrealized Unrealized Fair December 31, 2015 Available for sale securities: U.S. Treasury and U.S. government agencies $ 26,316 $ 729 $ 55 $ 26,990 Mortgage-backed U.S. government agencies 38,983 49 228 38,804 State and political subdivision obligations 64,780 1,914 77 66,617 Corporate debt securities 2,000 80 10 2,070 Equity securities 1,271 2 33 1,240 $ 133,350 $ 2,774 $ 403 $ 135,721
Schedule of Fair Value and Unrealized Loss on Investments in a Continuous Unrealized Loss Position		The following table presents gross unrealized losses and fair value of investments aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at December 31, 2016 and 2015. Less Than 12 Months 12 Months or More Total (Dollars in thousands) December 31, 2016 Number Fair Value Unrealized Number Fair Unrealized Number Fair Value Unrealized Available for sale securities: U.S. Treasury and U.S. government agencies 23 $ 43,698 $ 1,542 0 $ — $ — 23 $ 43,698 $ 1,542 Mortgage-backed U.S. government agencies 18 24,321 579 0 — — 18 24,321 579 State and political subdivision obligations 108 50,582 2,332 0 — — 108 50,582 2,332 Equity securities 0 — — 2 1,056 112 2 1,056 112 Total temporarily impaired available for sale securities 149 $ 118,601 $ 4,453 2 $ 1,056 $ 112 151 $ 119,657 $ 4,565 Less Than 12 Months 12 Months or More Total (Dollars in thousands) December 31, 2015 Number Fair Unrealized Number Fair Unrealized Number Fair Unrealized Available for sale securities: U.S. Treasury and U.S. government agencies 6 $ 6,259 $ 43 2 $ 1,383 $ 12 8 $ 7,642 $ 55 Mortgage-backed U.S. government agencies 13 12,759 124 11 6,282 104 24 19,041 228 State and political subdivision obligations 9 4,041 32 3 1,631 45 12 5,672 77 Corporate debt securities 1 990 10 0 — — 1 990 10 Equity securities 0 — — 2 615 33 2 615 33 Total temporarily impaired available for sale securities 29 $ 24,049 $ 209 18 $ 9,911 $ 194 47 $ 33,960 $ 403
Investments Classified by Contractual Maturity Date	The table below illustrates the maturity distribution of investment securities at amortized cost and fair value as of June 30, 2017. Available-for-sale Held-to-maturity (Dollars in thousands) Amortized Fair Value Amortized Fair June 30, 2017 Due in 1 year or less $ 1,293 $ 1,292 $ — $ — Due after 1 year but within 5 years 20,311 20,178 14,486 14,546 Due after 5 years but within 10 years 47,618 46,801 5,362 5,432 Due after 10 years 14,046 13,700 — — 83,268 81,971 19,848 19,978 Mortgage-backed securities 28,543 28,239 51,248 51,221 Equity securities 1,168 1,143 — — $ 112,979 $ 111,353 $ 71,096 $ 71,199	The table below is the maturity distribution of investment securities at amortized cost and fair value at December 31, 2016. December 31, 2016 (Dollars in thousands) Amortized Fair Value Due in 1 year or less $ 1,293 $ 1,305 Due after 1 year but within 5 years 19,656 19,471 Due after 5 years but within 10 years 66,084 63,895 Due after 10 years 23,566 22,179 110,599 106,850 Mortgage-backed securities 26,181 25,619 Equity securities 1,268 1,156 $ 138,048 $ 133,625
Schedule of Fair Value and Unrealized Loss on Investments in a Continuous Unrealized Loss Position	The following tables present gross unrealized losses and fair value of investments aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position at June 30, 2017 and December 31, 2016. Less Than 12 Months 12 Months or More Total (Dollars in thousands) Number Fair Unrealized Number Fair Unrealized Number Fair Unrealized June 30, 2017 Available-for-sale U.S. Treasury and U.S. government agencies 21 $ 39,077 $ 852 1 $ 2,694 $ 6 22 $ 41,771 $ 858 Mortgage-backed U.S. government agencies 18 26,466 291 1 535 16 19 27,001 307 State and political subdivision obligations 48 24,121 381 7 3,845 133 55 27,966 514 Equity securities 0 — — 1 550 40 1 550 40 Total temporarily impaired available- for-sale securities 87 89,664 1,524 10 7,624 195 97 97,288 1,719 Held-to-maturity U.S. Treasury and U.S. government agencies 2 4,991 5 0 — — 2 4,991 5 Mortgage-backed U.S. government agencies 14 22,879 99 0 — — 14 22,879 99 State and political subdivision obligations 3 1,536 9 0 — — 3 1,536 9 Total temporarily impaired held-to-maturity 19 29,406 113 0 — — 19 29,406 113 Total 106 $ 119,070 $ 1,637 10 $ 7,624 $ 195 116 $ 126,694 $ 1,832 Less Than 12 Months 12 Months or More Total (Dollars in thousands) Number Fair Unrealized Number Fair Unrealized Number Fair Unrealized December 31, 2016 Available-for-sale U.S. Treasury and U.S. government agencies 23 $ 43,698 $ 1,542 0 $ — $ — 23 $ 43,698 $ 1,542 Mortgage-backed U.S. government agencies 18 24,321 579 0 — — 18 24,321 579 State and political subdivision obligations 108 50,582 2,332 0 — — 108 50,582 2,332 Equity securities 0 — — 2 1,056 112 2 1,056 112 Total temporarily impaired available-for-sale 149 $ 118,601 $ 4,453 2 $ 1,056 $ 112 151 $ 119,657 $ 4,565

Loans and Allowance for Loan 43

Loans and Allowance for Loan and Lease Losses (Tables)	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Classes of the Loan Portfolio Summarized by the Aggregate Risk Rating	The classes of the loan portfolio, summarized by the pass rating (net of deferred fees and costs of $435,000 as of June 30, 2017 and $196,000 as of December 31, 2016), and the classified ratings of special mention, substandard, and doubtful within Mid Penn’s internal risk rating system as of June 30, 2017 and December 31, 2016, are as follows: (Dollars in thousands) Pass Special Mention Substandard Doubtful Total June 30, 2017 Commercial and industrial $ 175,700 $ 4,385 $ 1,283 $ — $ 181,368 Commercial real estate 473,078 1,757 7,306 — 482,141 Commercial real estate—construction 52,543 191 571 — 53,305 Lease financing 307 — — — 307 Residential mortgage 101,186 102 1,349 — 102,637 Home equity 38,154 124 393 — 38,671 Consumer 3,878 — — — 3,878 $ 844,846 $ 6,559 $ 10,902 $ — $ 862,307 (Dollars in thousands) Pass Special Mention Substandard Doubtful Total December 31, 2016 Commercial and industrial $ 170,780 $ 937 $ 801 $ — $ 172,518 Commercial real estate 437,592 1,683 7,249 — 446,524 Commercial real estate—construction 52,888 202 1,286 — 54,376 Lease financing 425 — — — 425 Residential mortgage 97,994 107 1,356 — 99,457 Home equity 37,242 142 224 — 37,608 Consumer 3,016 — — — 3,016 $ 799,937 $ 3,071 $ 10,916 $ — $ 813,924	The classes of the loan portfolio, summarized by the aggregate pass rating, net of deferred fees and costs of $196,000 and $178,000 as of December 31, 2016 and 2015, respectively, and the classified ratings of special mention, substandard, and doubtful within Mid Penn’s internal risk rating system as of December 31, 2016 and 2015, are noted below: (Dollars in thousands) December 31, 2016 Pass Special Mention Substandard Doubtful Total Commercial and industrial $ 170,780 $ 937 $ 801 $ — $ 172,518 Commercial real estate 437,592 1,683 7,249 — 446,524 Commercial real estate—construction 52,888 202 1,286 — 54,376 Lease financing 425 — — — 425 Residential mortgage 97,994 107 1,356 — 99,457 Home equity 37,242 142 224 — 37,608 Consumer 3,016 — — 3,016 $ 799,937 $ 3,071 $ 10,916 $ — $ 813,924 (Dollars in thousands) December 31, 2015 Pass Special Mention Substandard Doubtful Total Commercial and industrial $ 158,302 $ 1,289 $ 670 $ — $ 160,261 Commercial real estate 359,859 2,088 7,517 — 369,464 Commercial real estate—construction 65,665 2,403 — — 68,068 Lease financing 727 — — — 727 Residential mortgage 101,507 475 1,361 — 100,665 Home equity 32,928 261 222 — 33,411 Consumer 3,917 — — — 3,917 $ 722,905 $ 6,516 $ 9,770 $ — $ 736,513
Impaired Loans by Loan Portfolio Class	Impaired loans by loan portfolio class as of June 30, 2017 and December 31, 2016 are summarized as follows: June 30, 2017 December 31, 2016 (Dollars in thousands) Recorded Unpaid Related Recorded Unpaid Related With no related allowance recorded Commercial and industrial $ — $ 18 $ — $ 4 $ 9 $ — Commercial real estate: Commercial real estate 900 1,390 — 726 1,792 — Acquired with credit deterioration 573 573 — 842 842 — Commercial real estate—construction 331 334 618 618 Residential mortgage: Residential mortgage 902 931 — 848 882 — Acquired with credit deterioration 324 324 — 389 389 — Home equity 327 369 — 111 129 — With an allowance recorded Commercial and industrial $ — $ — $ — $ 56 $ 62 $ 6 Commercial real estate 2,751 2,915 893 2,520 2,646 711 Commercial real estate—construction 240 242 70 242 242 72 Residential mortgage 66 68 66 68 68 68 Home equity — — — 29 49 1 Total Impaired Loans Commercial and industrial $ — $ 18 $ — $ 60 $ 71 $ 6 Commercial real estate 4,224 4,878 893 4,088 5,280 711 Commercial real estate—construction 571 576 70 860 860 72 Residential mortgage 1,292 1,323 66 1,305 1,339 68 Home equity 327 369 — 140 178 1	Impaired loans by loan portfolio class as of December 31, 2016 and 2015 are summarized as follows: December 31, 2016 December 31, 2015 (Dollars in thousands) Recorded Unpaid Related Recorded Unpaid Related With no related allowance recorded: Commercial and industrial: Commercial and industrial $ 4 $ 9 $ — $ 14 $ 49 $ — Commercial real estate: Commercial real estate 726 1,792 — 1,023 2,020 — Acquired with credit deterioration* 842 842 — 931 931 — Commercial real estate—construction: Commercial real estate—construction 618 618 — — — — Residential mortgage: Residential mortgage 848 882 — 1,329 1,434 — Acquired with credit deterioration* 389 389 — 400 400 — Home equity: Home equity 111 129 — 115 137 — With an allowance recorded: Commercial and industrial $ 56 $ 62 $ 6 $ 113 $ 128 $ 51 Commercial real estate 2,520 2,646 711 1,947 1,981 429 Commercial real estate—construction 242 242 72 — — — Residential mortgage 68 68 68 32 32 23 Home equity 29 49 1 — — — Total: Commercial and industrial $ 60 $ 71 $ 6 $ 127 $ 177 $ 51 Commercial real estate 4,088 5,280 711 3,901 4,001 429 Commercial real estate—construction 860 860 72 — — — Residential mortgage 1,305 1,339 68 1,761 1,466 23 Home equity 140 178 1 115 137 —
Average Recorded Investment Of Impaired Loans And Related Interest Income By Loan Portfolio Class	The average recorded investment of impaired loans and related interest income recognized for the three and six months ended June 30, 2017 and 2016 are summarized as follows: Three Months Ended June 30, 2017 June 30, 2016 (Dollars in thousands) Average Interest Average Interest With no related allowance recorded Commercial and industrial $ 36 $ — $ 11 $ — Commercial real estate: Commercial real estate 644 — 960 — Acquired with credit deterioration 644 110 943 — Commercial real estate—construction 473 — — — Lease financing — Residential mortgage: Residential mortgage 860 7 831 7 Acquired with credit deterioration 326 2 377 Home equity: 66 — Home equity 90 — — — Acquired with credit deterioration — — — — Consumer — — — — With an allowance recorded Commercial and industrial $ — $ — $ 59 $ — Commercial real estate 2,792 — 2,201 — Commercial real estate—construction 240 — — — Lease financing — — — — Residential mortgage 66 — — — Home equity — — 17 — Consumer — — — — Total Impaired Loans Commercial and industrial $ 36 $ — $ 70 $ — Commercial real estate 4,080 110 4,104 — Commercial real estate—construction 713 — — — Lease financing — — — — Residential mortgage 1,252 9 1,208 7 Home equity 90 — 83 — Six Months Ended June 30, 2017 June 30, 2016 (Dollars in thousands) Average Interest Average Interest With no related allowance recorded Commercial and industrial $ 18 $ — $ 14 $ — Commercial real estate: Commercial real estate 524 279 1,001 — Acquired with credit deterioration 738 110 934 — Commercial real estate—construction 313 — — — Lease financing — — — — Residential mortgage: Residential mortgage 843 18 777 9 Acquired with credit deterioration 350 — 375 4 Home equity 101 2 53 — Consumer — With an allowance recorded Commercial and industrial $ — $ — $ 61 $ — Commercial real estate 2,660 — 1,851 — Commercial real estate—construction 144 — — — Lease financing — — — — Residential mortgage 40 — — — Home equity — — 19 — Consumer — — — — Total Impaired Loans Commercial and industrial $ 18 $ — $ 75 $ — Commercial real estate 3,922 389 3,786 — Commercial real estate—construction 457 — — — Lease financing — — — — Residential mortgage 1,233 18 1,152 13 Home equity 101 2 72 —	Average recorded investment of impaired loans and related interest income recognized for the years ended December 31, 2016, 2015, and 2014 are summarized as follows: December 31, 2016 December 31, 2015 December 31, 2014 (Dollars in thousands) Average Interest Average Interest Average Interest With no related allowance recorded: Commercial and industrial: Commercial and industrial $ 9 $ — $ 19 $ — $ 72 $ — Acquired with credit deterioration — — — 205 — — Commercial real estate: Commercial real estate 820 — 1,051 14 1,966 346 Acquired with credit deterioration 810 164 926 350 — — Commercial real estate—construction: Commercial real estate—construction 124 — — — — — Residential mortgage: Residential mortgage 821 21 816 8 541 — Acquired with credit deterioration 378 4 400 — — — Home equity: Home equity 75 — 107 — 29 — Acquired with credit deterioration — — — 3 — — With an allowance recorded: Commercial and industrial $ 59 $ — $ 123 $ — $ 93 $ — Commercial real estate 2,177 — 1,721 — 6,823 — Commercial real estate—construction 48 — — — — — Residential mortgage 14 — 25 — — — Home equity 32 — — — 76 — Total: Commercial and industrial $ 68 $ — $ 142 $ 205 $ 165 $ — Commercial real estate 3,807 164 3,698 364 8,789 346 Commercial real estate—construction 172 — — — — — Residential mortgage 1,213 25 1,241 8 541 — Home equity 107 — 107 3 105 —
Non-accrual Loans by Classes of the Loan Portfolio	Nonaccrual loans by loan portfolio class as of June 30, 2017 and December 31, 2016 are summarized as follows: (Dollars in thousands) June 30, 2017 December 31, 2016 Commercial and industrial $ — $ 4 Commercial real estate 3,630 2,939 Commercial real estate—construction 571 860 Residential mortgage 690 715 Home equity 327 140 $ 5,218 $ 4,658	Nonaccrual loans by loan portfolio class as of December 31, 2016 and 2015 are summarized as follows: (Dollars in thousands) 2016 2015 Commercial and industrial $ 4 $ 66 Commercial real estate 2,939 2,607 Commercial real estate—construction 860 — Residential mortgage 715 1,630 Home equity 140 115 $ 4,658 $ 4,418
Loan Portfolio Summarized by the Past Due Status	The classes of the loan portfolio summarized by the past due status as of June 30, 2017 and December 31, 2016 are summarized as follows: (Dollars in thousands) 30-59 60-89 Greater Total Current Total Loans June 30, 2017 Commercial and industrial $ 101 $ 4,083 $ — $ 4,184 $ 177,184 $ 181,368 $ — Commercial real estate: Commercial real estate 250 43 2,502 2,795 478,773 481,568 — Acquired with credit deterioration 516 — 57 573 — 573 57 Commercial real estate—construction 371 120 451 942 52,363 53,305 — Lease financing — — — — 307 307 — Residential mortgage: Residential mortgage 174 — 299 473 101,840 102,313 — Acquired with credit deterioration 32 — 226 258 66 324 — Home equity 13 — 298 311 38,360 38,671 — Consumer — — — — 3,878 3,878 — Total $ 1,457 $ 4,246 $ 3,833 $ 9,536 $ 852,771 $ 862,307 $ 57 (Dollars in thousands) 30-59 60-89 Greater Total Current Total Loans December 31, 2016 Commercial and industrial $ 164 $ 12 $ 4 $ 180 $ 172,338 $ 172,518 $ — Commercial real estate: Commercial real estate 475 — 1,004 1,479 444,203 445,682 — Acquired with credit deterioration — — 59 59 783 842 59 Commercial real estate—construction — 404 84 488 53,888 54,376 — Lease financing — — — — 425 425 — Residential mortgage: Residential mortgage 548 124 237 909 98,159 99,068 — Acquired with credit deterioration — — 238 238 151 389 — Home equity 33 13 125 171 37,437 37,608 — Consumer — — — — 3,016 3,016 — Total $ 1,220 $ 553 $ 1,751 $ 3,524 $ 810,400 $ 813,924 $ 59	The classes of the loan portfolio summarized by the past due status as of December 31, 2016 and 2015 are summarized as follows: (Dollars in thousands) December 31, 2016 30-59 60-89 Greater Total Current Total Loans Commercial and industrial: Commercial and industrial $ 164 $ 12 $ 4 $ 180 $ 172,338 $ 172,518 $ — Commercial real estate: Commercial real estate 475 — 1,004 1,479 444,203 445,682 — Acquired with credit deterioration — — 59 59 783 842 59 Commercial real estate—construction: Commercial real estate—construction — 404 84 488 53,888 54,376 — Lease financing: Lease financing — — — — 425 425 — Residential mortgage: Residential mortgage 548 124 237 909 98,159 99,068 — Acquired with credit deterioration — — 238 238 151 389 — Home equity: Home equity 33 13 125 171 37,437 37,608 — Consumer: Consumer — — — — 3,016 3,016 — Total $ 1,220 $ 553 $ 1,751 $ 3,524 $ 810,400 $ 813,924 $ 59 (Dollars in thousands) December 31, 2015 30-59 60-89 Greater Total Current Total Loans Commercial and industrial: Commercial and industrial $ 55 $ 204 $ 66 $ 325 $ 159,936 $ 160,261 $ — Commercial real estate: Commercial real estate 211 608 1,456 2,275 366,258 368,533 — Acquired with credit deterioration 215 518 55 788 143 931 55 Commercial real estate—construction: Commercial real estate—construction — — — — 68,068 68,068 — Lease financing: Lease financing — — — — 727 727 — Residential mortgage: Residential mortgage 694 550 778 2,022 98,243 100,265 — Acquired with credit deterioration 12 — 222 234 166 400 — Home equity: Home equity — 50 23 73 33,338 33,411 — Consumer: Consumer 10 5 — 15 3,902 3,917 — Total $ 1,197 $ 1,935 $ 2,600 $ 5,732 $ 730,781 $ 736,513 $ 55
Allowance and Recorded Investment in Financing Receivables	The following tables summarize the allowance and recorded investments in loans receivable. (Dollars in thousands) Commercial Commercial Commercial Lease Residential Home Consumer Unallocated Total As of, and for the three months ended, June 30, 2017 Allowance for loan and lease losses: Beginning balance, April 1, 2017 $ 1,630 $ 4,715 $ 101 $ 1 $ 532 $ 364 $ 3 $ 274 $ 7,620 Charge-offs — (30 ) — — — — (10 ) — (40 ) Recoveries 3 22 — — 2 5 1 — 33 Provisions (5 ) 274 39 — 5 35 10 (258 ) 100 Ending balance, June 30, 2017 $ 1,628 $ 4,981 $ 140 $ 1 $ 539 $ 404 $ 4 $ 16 $ 7,713 (Dollars in thousands) Commercial Commercial Commercial Lease Residential Home Consumer Unallocated Total As of, and for the six months ended, June 30, 2017 Allowance for loan and lease losses: Beginning balance, January 1, 2017 $ 1,580 $ 4,323 $ 144 $ 1 $ 541 $ 379 $ 3 $ 212 $ 7,183 Charge-offs (12 ) (30 ) — — (18 ) — (16 ) — (76 ) Recoveries 7 361 — — 4 5 4 — 381 Provisions 53 327 (4 ) — 12 20 13 (196 ) 225 Ending balance, June 30, 2017 1,628 4,981 140 1 539 404 4 16 7,713 Ending balance: individually evaluated for impairment — 893 70 — 66 — — — 1,029 Ending balance: collectively evaluated for impairment $ 1,628 $ 4,088 $ 70 $ 1 $ 473 $ 404 $ 4 $ 16 $ 6,684 Loans receivables: Ending balance $ 181,368 $ 482,141 $ 53,305 $ 307 $ 102,637 $ 38,671 $ 3,878 $ — $ 862,307 Ending balance: individually evaluated for impairment — 3,651 571 — 968 327 — — 5,517 Ending balance: acquired with credit deterioration — 573 — — 324 — — — 897 Ending balance: collectively evaluated for impairment $ 181,368 $ 477,917 $ 52,734 $ 307 $ 101,345 $ 38,344 $ 3,878 $ — $ 855,893 (Dollars in thousands) Commercial Commercial Commercial Lease Residential Home Consumer Unallocated Total As of, and for the three months ended, June 30, 2016 Allowance for loan and lease losses: Beginning balance, April 1, 2016 $ 1,427 $ 3,777 $ 119 $ 1 $ 516 $ 303 $ 9 $ 287 $ 6,439 Charge-offs — (54 ) — — — (25 ) (7 ) — (86 ) Recoveries 1 136 — — 25 — 2 — 164 Provisions (56 ) 382 1 — (20 ) 47 5 36 395 Ending balance, June 30, 2016 $ 1,372 $ 4,241 $ 120 $ 1 $ 521 $ 325 $ 9 $ 323 $ 6,912 (Dollars in thousands) Commercial Commercial Commercial Lease Residential Home Consumer Unallocated Total As of, and for the six months ended, June 30, 2016 Allowance for loan and lease losses: Beginning balance, January 1, 2016 $ 1,393 $ 3,552 $ 153 $ 1 $ 534 $ 317 $ 12 $ 206 $ 6,168 Charge-offs — (150 ) — — — (25 ) (10 ) — (185 ) Recoveries 2 161 — — 25 — 6 — 194 Provisions (23 ) 678 (33 ) — (38 ) 33 1 117 735 Ending balance, June 30, 2016 1,372 4,241 120 1 521 325 9 323 6,912 Ending balance: individually evaluated for impairment 3 769 — — — 2 — — 774 Ending balance: collectively evaluated for impairment $ 1,369 $ 3,472 $ 120 $ 1 $ 521 $ 323 $ 9 $ 323 $ 6,138 Loans receivables: Ending balance $ 160,278 $ 410,786 $ 56,074 $ 565 $ 103,822 $ 34,579 $ 3,049 $ — $ 769,153 Ending balance: individually evaluated for impairment 68 3,657 — — 824 81 — — 4,630 Ending balance: acquired with credit deterioration — 951 — — 370 — — — 1,321 Ending balance: collectively evaluated for impairment $ 160,210 $ 406,178 $ 56,074 $ 565 $ 102,628 $ 34,498 $ 3,049 $ — $ 763,202 (Dollars in thousands) Commercial Commercial Commercial Lease Residential Home Consumer Unallocated Total December 31, 2016 Allowance for loan and lease losses: Ending balance $ 1,580 $ 4,323 $ 144 $ 1 $ 541 $ 379 $ 3 $ 212 $ 7,183 Ending balance: individually evaluated for impairment 6 711 72 — 68 1 — — 858 Ending balance: collectively evaluated for impairment $ 1,574 $ 3,612 $ 72 $ 1 $ 473 $ 378 $ 3 $ 212 $ 6,325 Loans receivable: Ending balance $ 172,518 $ 446,524 $ 54,376 $ 425 $ 99,457 $ 37,608 $ 3,016 $ — $ 813,924 Ending balance: individually evaluated for impairment 60 3,246 860 — 916 140 — — 5,222 Ending balance: acquired with credit deterioration — 842 — — 389 — — — 1,231 Ending balance: collectively evaluated for impairment $ 172,458 $ 442,436 $ 53,516 $ 425 $ 98,152 $ 37,468 $ 3,016 $ — $ 807,471	Activity in the allowance for loan and lease losses for the years ended December 31, 2016, 2015, and 2014, and the recorded investment in loans receivable as of December 31, 2016, 2015, and 2014 are as follows: (Dollars in thousands) December 31, 2016 Commercial and industrial Commercial real estate Commercial real estate - construction Lease financing Residential mortgage Home equity Consumer Unallocated Total Allowance for loan and lease losses: Beginning balance $ 1,393 $ 3,552 $ 153 $ 1 $ 534 $ 317 $ 12 $ 206 $ 6,168 Charge-offs (820 ) (216 ) — — (4 ) (25 ) (42 ) — (1,107 ) Recoveries 4 211 — — 26 — 11 — 252 Provisions 1,003 776 (9 ) — (15 ) 87 22 6 1,870 Ending balance 1,580 4,323 144 1 541 379 3 212 7,183 Ending balance: individually evaluated for impairment 6 711 72 — 68 1 — — 858 Ending balance: collectively evaluated for impairment $ 1,574 $ 3,612 $ 72 $ 1 $ 473 $ 378 $ 3 $ 212 $ 6,325 Loans receivable: Ending balance $ 172,518 $ 446,524 $ 54,376 $ 425 $ 99,457 $ 37,608 $ 3,016 $ — $ 813,924 Ending balance: individually evaluated for impairment 60 3,246 860 — 916 140 — — 5,222 Ending balance: acquired with credit deterioration — 842 — — 389 — — — 1,231 Ending balance: collectively evaluated for impairment $ 172,458 $ 442,436 $ 53,516 $ 425 $ 98,152 $ 37,468 $ 3,016 $ — $ 807,471 (Dollars in thousands) December 31, 2015 Commercial Commercial Commercial real estate - Lease Residential Home Consumer Unallocated Total Allowance for loan and lease losses: Beginning balance $ 1,393 $ 3,925 $ 33 $ 2 $ 450 $ 653 $ 35 $ 225 $ 6,716 Charge-offs (130 ) (1,569 ) — — (35 ) (36 ) (14 ) — (1,784 ) Recoveries 12 75 — — 44 29 11 — 171 Provisions 118 1,121 120 (1 ) 75 (329 ) (20 ) (19 ) 1,065 Ending balance 1,393 3,552 153 1 534 317 12 206 6,168 Ending balance: individually evaluated for impairment 51 429 — — 23 — — — 503 Ending balance: collectively evaluated for impairment $ 1,342 $ 3,123 $ 153 $ 1 $ 511 $ 317 $ 12 $ 206 $ 5,665 Loans receivable: Ending balance $ 160,261 $ 369,464 $ 68,068 $ 727 $ 100,665 $ 33,411 $ 3,917 $ — $ 736,513 Ending balance: individually evaluated for impairment 127 2,970 — — 1,361 115 — — 4,573 Ending balance: acquired with credit deterioration — 931 — — 400 — — — 1,331 Ending balance: collectively evaluated for impairment $ 160,134 $ 365,563 $ 68,068 $ 727 $ 98,904 33,296 $ 3,917 $ — $ 730,609 (Dollars in thousands) December 31, 2014 Commercial and industrial Commercial real estate Commercial real estate - construction Lease financing Residential mortgage Home equity Consumer Unallocated Total Allowance for loan and lease losses: Beginning Balance $ 1,187 $ 4,006 $ 9 $ — $ 581 $ 441 $ 72 $ 21 $ 6,317 Charge-offs (62 ) (1,057 ) — — (133 ) (43 ) (33 ) — (1,328 ) Recoveries 13 13 — — 20 1 63 — 110 Provisions 255 963 24 2 (18 ) 254 (67 ) 204 1,617 Ending balance 1,393 3,925 33 2 450 653 35 225 6,716 Ending balance: individually evaluated for impairment 137 1,382 — — — 115 — — 1,634 Ending balance: collectively evaluated for impairment $ 1,256 $ 2,543 $ 33 $ 2 $ 450 $ 538 $ 35 $ 225 $ 5,082 Loans receivable: Ending balance $ 119,010 $ 297,357 $ 56,076 $ 1,121 $ 66,442 $ 28,506 $ 3,021 $ — $ 571,533 Ending balance: individually evaluated for impairment 618 8,925 — — 1,146 240 — — 10,929 Ending balance: collectively evaluated for impairment $ 118,392 $ 288,432 $ 56,076 $ 1,121 $ 65,296 $ 28,266 $ 3,021 $ — $ 560,604
Troubled Debt Restructurings	The recorded investments in troubled debt restructured loans at June 30, 2017 and December 31, 2016 are as follows: (Dollars in thousands) Pre-Modification Post-Modification Recorded Investment June 30, 2017 Commercial real estate $ 3,457 $ 4,003 $ 2,407 Residential mortgage 759 743 623 $4,216 $4,746 $3,030 (Dollars in thousands) Pre-Modification Post-Modification Recorded Investment December 31, 2016 Commercial and industrial $ 40 $ 35 $ 5 Commercial real estate 4,569 4,031 2,871 Residential mortgage 759 757 639 $ 5,368 $ 4,823 $ 3,515	The recorded investments in troubled debt restructured loans at December 31, 2016 and 2015 are as follows: Pre-Modification Post-Modification (Dollars in thousands) December 31, 2016 Outstanding Recorded Investment Outstanding Recorded Investment Recorded Investment Commercial and industrial $ 40 $ 35 $ 5 Commercial real estate 4,569 4,031 2,871 Residential mortgage 759 757 639 $ 5,368 $ 4,823 $ 3,515 Pre-Modification Post-Modification (Dollars in thousands) December 31, 2015 Outstanding Recorded Investment Outstanding Recorded Investment Recorded Investment Commercial and industrial $ 40 $ 35 $ 15 Commercial real estate 3,634 3,117 2,235 Residential mortgage 733 727 555 $ 4,407 $ 3,879 $ 2,805
Schedule of Troubled Debt Restructurings Modified in the Period		The following table summarizes the loans whose terms have been modified resulting in troubled debt restructurings during the year ended December 31, 2016. (Dollars in thousands) December 31, 2016 Number Pre- Post- Recorded Commercial real estate 2 $ 934 $ 914 $ 914 Residential mortgage 1 68 68 68 3 $ 1,002 $ 982 $ 982
Schedule of Accretion of Purchased Impaired Loan	The following tables provide activity for the accretable yield of acquired impaired loans for the three and six months ended June 30, 2017. (Dollars in thousands) Accretable yield, April 1, 2017 $ 80 Accretable yield amortized to interest income (12 ) Reclassification from nonaccretable difference (a) — Accretable yield, June 30, 2017 $ 68 (Dollars in thousands) Accretable yield, January 1, 2017 $ 67 Accretable yield amortized to interest income (22 ) Reclassification from nonaccretable difference (a) 23 Accretable yield, June 30, 2017 $ 68 (a) Reclassification from non-accretable difference represents an increase to the estimated cash flows to be collected on the underlying portfolio.	The following table provides activity for the accretable yield of purchased impaired loans for the year ended December 31, 2016. (Dollars in thousands) Accretable yield, January 1, 2016 $ 178 Accretable yield amortized to interest income (141 ) Reclassification from nonaccretable difference (a) 30 Accretable yield, December 31, 2016 $ 67 (a) Reclassification from non-accretable difference represents an increase to the estimated cash flows to be collected on the underlying portfolio.

Bank Premises and Equipment (Ta

Bank Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Premises and Equipment	At December 31, 2016 and 2015, bank premises and equipment are as follows: (Dollars in thousands) 2016 2015 Land $ 2,315 $ 2,906 Buildings 9,517 10,789 Furniture, fixtures, and equipment 8,184 8,742 Leasehold improvements 1,432 1,212 Construction in progress 89 18 Total cost 21,537 23,667 Less accumulated depreciation (10,463 ) (9,674 ) Net book value of bank premises and equipment 11,074 13,993 Assets held for sale 1,894 — Total bank premises and equipment $ 12,968 $ 13,993
Schedule of Future Minimum Rental Payments of Operating Leases	The following summary reflects the future minimum rental payments by year under Mid Penn’s operating leases as of December 31, 2016, including a breakdown of the sublease rental income and future minimum payments owed to related parties. (Dollars in thousands) Lease Obligation Sublease Rental Income Net Rental Expense 2017 $ 1,121 $ 74 $ 1,047 2018 1,115 79 1,036 2019 1,116 81 1,035 2020 793 81 712 2021 582 20 562 thereafter 5,666 — 5,666 $ 10,393 $ 335 $ 10,058

Deposits (Tables)

Deposits (Tables)	12 Months Ended
	Dec. 31, 2016
Deposits [Abstract]
Time Deposits By Maturity Date	Time deposits at December 31, 2016, mature as follows: Time Deposits (Dollars in thousands) Less than $250,000 $250,000 or more Maturing in 2017 $ 64,993 $ 16,760 Maturing in 2018 35,238 5,360 Maturing in 2019 20,094 3,209 Maturing in 2020 20,997 950 Maturing in 2021 13,953 303 Maturing thereafter 738 — $ 156,013 $ 26,582

Long-term Debt (Tables)

Long-term Debt (Tables)	12 Months Ended
	Dec. 31, 2016
Maturities of Long-term Debt [Abstract]
Long-term Debt Outstanding by Maturity Date	As of December 31, 2016 and 2015, the Bank had long-term At December 31, (Dollars in thousands) 2016 2015 Loans maturing in 2016 with rates ranging from 0.54% to 1.08% $ — $ 26,521 Loans maturing in 2017 at a rate of 3.03% 1,016 1,016 Loan maturing in 2019 at a rate of 1.87% 10,000 10,000 Loan maturing in 2026 at a rate of 4.80% 2,504 2,703 Loan maturing in 2027 at a rate of 6.71% 61 65 $ 13,581 $ 40,305

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Assets Measured at Fair Value on a Recurring Basis	The following tables illustrate the assets measured at fair value on a recurring basis segregated by hierarchy fair value levels. Fair value measurements at June 30, 2017 (Dollars in thousands) Total carrying value at Quoted prices Significant observable Significant unobservable inputs Assets: June 30, 2017 (Level 1) (Level 2) (Level 3) Available-for-sale U.S. Treasury and U.S. government agencies $ 41,771 $ — $ 41,771 $ — Mortgage-backed U.S. government agencies 28,239 — 28,239 — State and political subdivision obligations 39,095 — 39,095 — Corporate debt securities 1,105 1,105 Equity securities 1,143 1,143 — — Total $ 111,353 $ 1,143 $ 110,210 $ — Fair value measurements at December 31, 2016 (Dollars in thousands) Total carrying value at Quoted prices Significant observable Significant unobservable inputs Assets: December 31, 2016 (Level 1) (Level 2) (Level 3) Available-for-sale U.S. Treasury and U.S. government agencies $ 47,012 $ 1,864 $ 45,148 $ — Mortgage-backed U.S. government agencies 25,619 — 25,619 — State and political subdivision obligations 58,838 — 58,838 — Corporate debt securities 1,100 — 1,100 Equity securities 1,056 1,056 — — Total $ 133,625 $ 2,920 $ 130,705 $ —	The following tables illustrate the assets measured at fair value on a recurring basis segregated by hierarchy fair value levels: Fair value measurements at December 31, Total carrying value at Quoted prices in active markets Significant other observable inputs Significant unobservable inputs (Dollars in thousands) December 31, 2016 (Level 1) (Level 2) (Level 3) Assets: U.S. Treasury and U.S. government agencies $ 47,012 $ 1,864 $ 45,148 $ — Mortgage-backed U.S. government agencies 25,619 — 25,619 — State and political subdivision obligations 58,838 — 58,838 — Corporate debt securities 1,000 — 1,000 — Equity securities 1,156 1,056 100 — $ 133,625 $ 2,920 $ 130,705 $ — Fair value measurements at Total carrying value at Quoted prices in active markets Significant other observable inputs Significant unobservable inputs (Dollars in thousands) December 31, 2015 (Level 1) (Level 2) (Level 3) Assets: U.S. Treasury and U.S. government agencies $ 26,990 $ 1,861 $ 25,129 $ — Mortgage-backed U.S. government agencies 38,804 — 38,804 — State and political subdivision obligations 66,617 — 66,617 — Corporate debt securities 2,070 — 2,070 — Equity securities 1,240 1,240 — — $ 135,721 $ 3,101 $ 132,620 $ —
Fair Value Measurements, Nonrecurring	The following tables illustrate the assets measured at fair value on a nonrecurring basis segregated by hierarchy fair value levels. Fair value measurements at June 30, 2017 (Dollars in thousands) Assets: Total Quoted prices Significant Significant Impaired Loans $ 2,061 $ — $ — $ 2,061 Foreclosed Assets Held for Sale — — — — Mortgage Servicing Rights 135 — — 135 Fair value measurements at December 31, (Dollars in thousands) Assets: Total Quoted prices Significant Significant Impaired Loans $ 2,404 $ — $ — $ 2,404 Foreclosed Assets Held for Sale 135 — — 135 Mortgage Servicing Rights 144 — — 144	The following tables illustrate the assets measured at fair value on a nonrecurring basis segregated by hierarchy fair value levels. Fair value measurements at December 31, (Dollars in thousands) Total carrying value at Quoted prices in active markets Significant other observable inputs Significant unobservable inputs December 31, 2016 (Level 1) (Level 2) (Level 3) Assets: Impaired Loans $ 2,404 $ — $ — $ 2,404 Foreclosed Assets Held for Sale 135 — — 135 Mortgage Servicing Rights 144 — — 144 Fair value measurements at December 31, (Dollars in thousands) Total carrying value at Quoted prices in active markets Significant other observable inputs Significant unobservable inputs December 31, 2015 (Level 1) (Level 2) (Level 3) Assets: Impaired Loans $ 2,088 $ — $ — $ 2,088 Foreclosed Assets Held for Sale 453 — — 453 Mortgage Servicing Rights 174 — — 174
Fair Value Inputs, Assets, Quantitative Information	The following tables present additional quantitative information about assets measured at fair value on a nonrecurring basis and for which Mid Penn has utilized Level 3 inputs to determine the fair value. (Dollars in thousands) Quantitative Information about Level 3 Fair Value Measurements June 30, 2017 Fair Value Valuation Technique Unobservable Input Range Weighted Impaired Loans $ 2,061 Appraisal of collateral (a) Appraisal adjustments (b) 26% - 43% 35% Foreclosed Assets Held for Sale — Appraisal of collateral (a), (c) Appraisal adjustments (b) 0% - 0% 0% Mortgage Servicing Rights 135 Multiple of annual service fee Estimated prepayment speed based on rate and term 210% - 400% 365% (Dollars in thousands) Quantitative Information about Level 3 Fair Value Measurements December 31, 2016 Fair Value Valuation Technique Unobservable Input Range Weighted Impaired Loans $ 2,404 Appraisal of collateral (a) Appraisal adjustments (b) 11% - 70% 30% Foreclosed Assets Held for Sale 135 Appraisal of collateral (a), (c) Appraisal adjustments (b) 26% - 31% 27% Mortgage Servicing Rights 144 Multiple of annual service fee Estimated prepayment speed based on rate and term 210% - 400% 365% (a) Fair value is generally determined through independent appraisals of the underlying collateral, which generally includes various level 3 inputs which are not observable. (b) Appraisals may be adjusted downward by management for qualitative factors such as economic conditions and estimated liquidation expenses. The range of liquidation expenses and other appraisal adjustments are presented as a percent of the appraisal. Higher downward adjustments are caused by negative changes to the collateral or conditions in the real estate market, actual offers or sales contracts received, or age of the appraisal. (c) Includes qualitative adjustments by management and estimated liquidation expenses.	The following tables present additional quantitative information about assets measured at fair value on a nonrecurring basis and for which Mid Penn has utilized Level 3 inputs to determine the fair value. Quantitative Information about Level 3 Fair Value Measurements (Dollars in thousands) December 31, 2016 Fair Value Estimate Valuation Technique Unobservable Input Range Weighted Average Impaired Loans $ 2,404 Appraisal of collateral (a) Appraisal adjustments (b) 11% -70% 30% Foreclosed Assets Held for Sale 135 Appraisal of collateral (a), (c) Appraisal adjustments (b) 26% - 31% 27% Mortgage Servicing Rights 144 Multiple of annual service fee Estimated prepayment speed based on rate and term 210% - 400% 365% Quantitative Information about Level 3 Fair Value Measurements (Dollars in thousands) December 31, 2015 Fair Value Estimate Valuation Technique Unobservable Input Range Weighted Average Impaired Loans $ 2,088 Appraisal of collateral (a) Appraisal adjustments (b) 11% - 60% 30% Foreclosed Assets Held for Sale 453 Appraisal of collateral (a), (c) Appraisal adjustments (b) 17% - 27% 26% Mortgage Servicing Rights 174 Multiple of annual service fee Estimated prepayment speed based on rate and term 210% - 400% 360% (a) Fair value is generally determined through independent appraisals of the underlying collateral, which generally includes various level 3 inputs which are not observable. (b) Appraisals may be adjusted downward by management for qualitative factors such as economic conditions and estimated liquidation expenses. The range of liquidation expenses and other appraisal adjustments are presented as a percent of the appraisal. Higher downward adjustments are caused by negative changes to the collateral or conditions in the real estate market, actual offers or sales contracts received, or age of the appraisal. (c) Includes qualitative adjustments by management and estimated liquidation expenses.
Fair Value, by Balance Sheet Grouping	The following table summarizes the carrying value and fair value of financial instruments at June 30, 2017 and December 31, 2016. (Dollars in thousands) June 30, 2017 December 31, 2016 Carrying Fair Carrying Fair Financial assets: Cash and cash equivalents $ 29,179 $ 29,179 $ 45,973 $ 45,973 Available-for-sale 111,353 111,353 133,625 133,625 Held-to-maturity 71,096 71,199 — — Loans held for sale 2,369 2,369 1,959 1,959 Net loans and leases 854,594 874,192 806,741 824,293 Restricted investment in bank stocks 3,985 3,985 2,443 2,443 Accrued interest receivable 3,991 3,991 3,928 3,928 Mortgage servicing rights 135 135 144 144 Financial liabilities: Deposits $ 987,468 $ 988,200 $ 935,373 $ 935,075 Short-term borrowings 21,468 21,468 — — Long-term debt 13,467 12,149 13,581 13,614 Subordinated debt 7,419 7,420 7,414 7,534 Accrued interest payable 788 788 515 515 Off-balance Commitments to extend credit $ — $ — $ — $ — Financial standby letters of credit — — — —	The following table summarizes the carrying value and fair value of financial instruments at December 31, 2016 and 2015. (Dollars in thousands) December 31, 2016 December 31, 2015 Carrying Fair Value Carrying Fair Value Financial assets: Cash and cash equivalents $ 45,973 $ 45,973 $ 13,284 $ 13,284 Interest-bearing time balances with other financial institutions — — 4,317 4,317 Available for sale investment securities 133,625 133,625 135,721 135,721 Net loans and leases 806,741 824,293 730,345 738,773 Restricted investment in bank stocks 2,443 2,443 4,266 4,266 Accrued interest receivable 3,928 3,928 3,813 3,813 Mortgage servicing rights 144 144 174 174 Financial liabilities: Deposits $ 935,373 $ 935,075 $ 777,043 $ 777,320 Short-term borrowings — — 31,596 31,596 Long-term debt 13,581 13,614 40,305 39,626 Subordinated debt 7,414 7,534 7,500 7,500 Accrued interest payable 515 515 390 390 Off-balance sheet financial instruments: Commitments to extend credit $ — $ — $ — $ — Financial standby letters of credit — — — —
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following tables present the carrying amount, fair value, and placement in the fair value hierarchy of Mid Penn’s financial instruments as of June 30, 2017 and December 31, 2016. Fair Value Measurements (Dollars in thousands) June 30, 2017 Carrying Fair Value Quoted Prices in Significant Significant Financial instruments—assets Held-to-maturity $ 71,096 $ 71,199 $ — $ 71,199 $ — Net loans and leases 854,594 874,192 — — 874,192 Financial instruments—liabilities Deposits $ 987,468 $ 988,200 $ — $ 988,200 $ — Short-term borrowings 21,468 21,468 21,468 Long-term debt 13,467 12,149 — 12,149 — Subordinated debt 7,419 7,420 — 7,420 — Fair Value Measurements (Dollars in thousands) December 31, 2016 Carrying Fair Value Quoted Prices in Significant Significant Financial instruments—assets Net loans and leases $ 806,741 $ 824,293 $ — $ — $ 824,293 Financial instruments—liabilities Deposits $ 935,373 $ 935,075 $ — $ 935,075 $ — Long-term debt 13,581 13,614 — 13,614 — Subordinated debt $ 7,414 $ 7,534 $ 7,534	The following presents the carrying amount, fair value, and placement in the fair value hierarchy of Mid Penn’s financial instruments as of December 31, 2016 and 2015. Carrying values approximate fair values for cash and cash equivalents, interest-bearing time balances with other financial institutions, restricted investment in bank stocks, mortgage servicing rights, accrued interest receivable and payable, short-term borrowings, and subordinated debt. Other than cash and cash equivalents, which are considered Level 1 Inputs, these instruments are Level 2 Inputs. The following tables exclude financial instruments for which the placement in the fair value hierarchy has been disclosed elsewhere or for which the carrying amount approximates fair value. Fair Value Measurements (Dollars in thousands) December 31, 2016 Carrying Fair Value Quoted Prices in Significant Other Significant Financial instruments—assets Net loans and leases $ 806,741 $ 824,293 $ — $ — $ 824,293 Financial instruments—liabilities Deposits $ 935,373 $ 935,075 $ — $ 935,075 $ — Long-term debt 13,581 13,614 — 13,614 — Fair Value Measurements (Dollars in thousands) December 31, 2015 Carrying Fair Value Quoted Prices in Significant Other Significant (Level 3) Financial instruments—assets Net loans and leases $ 730,345 $ 738,773 $ — $ — $ 738,773 Financial instruments—liabilities Deposits $ 777,043 $ 777,320 $ — $ 777,320 $ — Long-term debt 40,305 39,626 — 39,626 —

Defined Benefit Plans (Tables)

Defined Benefit Plans (Tables)	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Schedule of Amounts Recognized in Balance Sheet		The amount recognized in the consolidated balance sheet at December 31, 2016 and 2015, is as follows: (Dollars in thousands) 2016 2015 Accrued benefit liability $ 540 $ 572
Schedule of Amounts Recognized in Other Comprehensive (Loss) Income		The amounts recognized in accumulated other comprehensive (loss) income consist of: December 31, (Dollars in thousands) 2016 2015 Net gain, pretax $ (31 ) $ (47 ) Net prior service cost, pretax (209 ) (244 )
Schedule of Net Periodic (Income) Benefit Costs	The components of net periodic benefit costs from these defined benefit plans are as follows: Three Months Ended June 30, (Dollars in thousands) Pension Benefits Other Benefits 2017 2016 2017 2016 Service cost $ 9 $ 8 $ 1 $ 1 Interest cost 11 11 5 5 Amortization (accretion) of prior service cost 4 8 (6 ) 6 Net periodic benefit cost $ 24 $ 27 $ — $ 12 Six Months Ended June 30, (Dollars in thousands) Pension Benefits Other Benefits 2017 2016 2017 2016 Service cost $ 18 $ 17 $ 2 $ 2 Interest cost 22 23 10 11 Amortization (accretion) of prior service cost 7 25 (12 ) 91 Net periodic benefit cost $ 47 $ 65 $ — $ 104	The components of net periodic postretirement (income) benefit cost for 2016, 2015 and 2014 are as follows: (Dollars in thousands) 2016 2015 2014 Service cost $ 4 $ 13 $ 13 Interest cost 23 32 38 Amortization of prior service cost (35 ) — (1 ) Net periodic postretirement (income) benefit cost $ (8 ) $ 45 $ 50
Schedule of Assumptions Used		Assumptions used in the measurement of Mid Penn’s benefit obligations at December 31, 2016 and 2015 are as follows: 2016 2015 Weighted-average assumptions: Discount rate 4.00 % 4.25 % Rate of compensation increase 3.00 % 3.25 % Assumptions used in the measurement of Mid Penn’s net periodic benefit cost for the years ended December 31, 2016, 2015 and 2014 are as follows: 2016 2015 2014 Weighted-average assumptions: Discount rate 4.25 % 4.00 % 4.75 % Rate of compensation increase 3.25 % 3.00 % 3.75 %
Schedule of Health Care Cost Trend Rates		Assumed health care cost trend rates at December 31, 2016, 2015 and 2014 are as follows: 2016 2015 2014 Health care cost trend rate assumed for next year 6.00 % 5.50 % 6.50 % Rate to which the cost trend rate is assumed to decline (the ultimate trend rate) 5.50 % 5.50 % 5.50 % Year that the rate reaches the ultimate trend rate 2018 2016 2016
Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates		Assumed health care cost trend rates have a significant effect on the amounts reported for the health care Plans. At December 31, 2016, a one-percentage-point change in assumed health care cost trend rates would have the following effects: One-Percentage Point (Dollars in thousands) Increase Decrease Effect on total of service and interest cost $ — $ — Effect on accumulated postretirement benefit obligation 3 3
Schedule of Expected Benefit Payments		Mid Penn expects to contribute $73,000 to its life and health benefit Plans in 2017. The following table shows the estimated benefit payments for future periods. (Dollars in thousands) 1/1/2017 to 12/31/2017 $ 73 1/1/2018 to 12/31/2018 64 1/1/2019 to 12/31/2019 61 1/1/2020 to 12/31/2020 56 1/1/2021 to 12/31/2021 30 1/1/2022 to 12/31/2026 156
Defined Benefit Postretirement Health And Life Coverage [Member]
Schedule of Net Funded Status		The following tables provide a reconciliation of the changes in the Plan’s health and life insurance benefit obligations and fair value of Plan assets for the years ended December 31, 2016 and 2015, and a statement of the funded status at December 31, 2016 and 2015. December 31, (Dollars in thousands) 2016 2015 Change in benefit obligations: Benefit obligations, January 1 $ 572 $ 861 Service cost 4 13 Interest cost 23 32 Change in experience 2 (24 ) Change in assumptions 13 (4 ) Change due to plan amendment — (244 ) Benefit payments (74 ) (62 ) Benefit obligations, December 31 $ 540 $ 572 Change in fair value of plan assets: Fair value of plan assets, January 1 $ — $ — Employer contributions 74 62 Benefit payments (74 ) (62 ) Fair value of plan assets, December 31 $ — $ — Funded status at year end $ (540 ) $ (572 )
Director's Retirement Plan [Member]
Schedule of Net Funded Status		The following tables provide a reconciliation of the changes in the directors’ defined benefit Plan’s benefit obligations and fair value of Plan assets for the years ended December 31, 2016 and 2015 and a statement of the status at December 31, 2016 and 2015. This Plan is unfunded. December 31, (Dollars in thousands) 2016 2015 Change in benefit obligations: Benefit obligations, January 1 $ 1,150 $ 1,186 Service cost 34 33 Interest cost 46 45 Actuarial gain (13 ) (8 ) Change in assumptions (4 ) (16 ) Benefit payments (91 ) (90 ) Benefit obligations, December 31 $ 1,122 $ 1,150 Change in fair value of plan assets: Fair value of plan assets, January 1 $ — $ — Employer contributions 91 90 Benefit payments (91 ) (90 ) Fair value of plan assets, December 31 $ — $ — Funded status at year end $ (1,122 ) $ (1,150 )
Schedule of Amounts Recognized in Balance Sheet		Amounts recognized in the consolidated balance sheet at December 31, 2016 and 2015 are as follows: (Dollars in thousands) 2016 2015 Accrued benefit liability $ 1,122 $ 1,150
Schedule of Amounts Recognized in Other Comprehensive (Loss) Income		Amounts recognized in accumulated other comprehensive income (loss) consist of: December 31, (Dollars in thousands) 2016 2015 Net prior service cost, pretax $ 43 $ 64 Net loss, pretax 60 77
Schedule of Net Periodic (Income) Benefit Costs		The components of net periodic retirement cost for 2016, 2015 and 2014 are as follows: (Dollars in thousands) 2016 2015 2014 Service cost $ 34 $ 33 $ 33 Interest cost 46 45 51 Amortization of prior-service cost 22 22 22 Net periodic retirement cost $ 102 $ 100 $ 106
Schedule of Assumptions Used		Assumptions used in the measurement of Mid Penn’s benefit obligations at December 31, 2016 and 2015 are as follows: 2016 2015 Weighted-average assumptions: Discount rate 4.00 % 4.25 % Change in consumer price index 2.00 % 2.25 % Assumptions used in the measurement of Mid Penn’s net periodic benefit cost for the years ended December 31, 2016, 2015 and 2014 are as follows: 2016 2015 2014 Weighted-average assumptions: Discount rate 4.25 % 4.00 % 4.75 % Change in consumer price index 2.25 % 2.25 % 2.75 %
Schedule of Expected Benefit Payments		Mid Penn expects to contribute $94,000 to its retirement Plan in 2017. The following table shows the estimated benefit payments for future periods. (Dollars in thousands) 1/1/2017 to 12/31/2017 $ 94 1/1/2018 to 12/31/2018 96 1/1/2019 to 12/31/2019 96 1/1/2020 to 12/31/2020 98 1/1/2021 to 12/31/2021 108 1/1/2022 to 12/31/2026 464

Other Benefit Plans (Tables)

Other Benefit Plans (Tables)	12 Months Ended
	Dec. 31, 2016
Defined Contribution Pension And Other Postretirement Plans Disclosure Abstract
Schedule of Employees Eligible to Participate in Employee Stock Purchase Plan	Mid Penn has an Employee Stock Purchase Plan (“ESPP”) in which all employees are eligible to participate. The Plan allows employees to use a portion of their salaries and wages to purchase common shares of Mid Penn stock at the market value of shares at the end of each calendar quarter. 2016 2015 2014 ESPP shares purchased 4,465 4,162 3,432 Average purchase price per share $ 18.520 $ 15.865 $ 15.318

Federal Income Taxes (Tables)

Federal Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Net Deferred Tax Asset	The following temporary differences gave rise to the net deferred tax asset at December 31, 2016 and 2015. (Dollars in thousands) 2016 2015 Deferred tax assets: Allowance for loan and lease losses $ 2,442 $ 2,097 Loan fees 82 79 Deferred compensation 906 313 Benefit plans 955 586 Unrealized loss on securities 1,504 — Nonaccrual interest — 554 Business combination adjustments 720 1,166 Other 177 170 6,786 4,965 Deferred tax liabilities: Depreciation (1,175 ) (1,074 ) Bond accretion (117 ) (111 ) Goodwill and intangibles (500 ) (472 ) Unrealized gain on securities — (806 ) Prepaid expenses (312 ) (240 ) Business combination adjustments (367 ) (428 ) Other (29 ) (13 ) (2,500 ) (3,144 ) Deferred tax asset, net $ 4,286 $ 1,821
Provision for Income Taxes	The provision for income taxes consists of the following: (Dollars in thousands) 2016 2015 2014 Current expense $ 2,613 $ 647 $ 1,574 Deferred (benefit) expense (336 ) 997 (112 ) Total provision for income taxes $ 2,277 $ 1,644 $ 1,462
Schedule of Effective Income Tax Rate Reconciliation	A reconciliation of income tax at the statutory rate of 34% to Mid Penn’s effective rate is as follows: (Dollars in thousands) 2016 2015 2014 Provision at the expected statutory rate $ 3,428 $ 2,779 $ 2,435 Effect of tax-exempt income (1,089 ) (1,105 ) (1,086 ) Effect of investment in life insurance (90 ) (91 ) (68 ) Nondeductible interest 41 37 42 Nondeductible merger and acquisition expense — 34 163 Other items (13 ) (10 ) (24 ) Provision for income taxes $ 2,277 $ 1,644 $ 1,462

Regulatory Matters (Tables)

Regulatory Matters (Tables)	12 Months Ended
	Dec. 31, 2016
Regulatory Capital Requirements [Abstract]
Regulatory Capital Levels and Related Ratios	Mid Penn maintained the following regulatory capital levels, leverage ratios, and risk-based capital ratios as of December 31, 2016, and December 31, 2015, as follows: Capital Adequacy Actual Minimum Capital To Be Well-Capitalized (Dollars in thousands) Amount Ratio Amount Ratio Amount Ratio Corporation As of December 31, 2016 Tier 1 Capital (to Average Assets) $ 70,431 6.8 % $ 41,595 4.0 % $ N/A N/A Common Equity Tier 1 Capital (to Risk Weighted Assets) 70,431 9.1 % 34,807 4.5 % N/A N/A Tier 1 Capital (to Risk Weighted Assets) 70,431 9.1 % 46,409 6.0 % N/A N/A Total Capital (to Risk Weighted Assets) 85,148 11.0 % 61,879 8.0 % N/A N/A Bank As of December 31, 2016 Tier 1 Capital (to Average Assets) $ 77,026 7.4 % $ 41,568 4.0 % $ 51,960 5.0 % Common Equity Tier 1 Capital (to Risk Weighted Assets) 77,026 10.0 % 34,781 4.5 % 50,239 6.5 % Tier 1 Capital (to Risk Weighted Assets) 77,026 10.0 % 46,374 6.0 % 61,832 8.0 % Total Capital (to Risk Weighted Assets) 84,329 10.9 % 61,832 8.0 % 77,291 10.0 % Corporation As of December 31, 2015 Tier 1 Capital (to Average Assets) $ 64,089 7.3 % $ 35,098 4.0 % $ N/A N/A Common Equity Tier 1 Capital (to Risk Weighted Assets) 64,089 9.1 % 31,731 4.5 % N/A N/A Tier 1 Capital (to Risk Weighted Assets) 64,089 9.1 % 42,308 6.0 % N/A N/A Total Capital (to Risk Weighted Assets) 77,852 11.0 % 56,410 8.0 % N/A N/A Bank As of December 31, 2015 Tier 1 Capital (to Average Assets) $ 70,351 7.8 % $ 36,245 4.0 % $ 45,306 5.0 % Common Equity Tier 1 Capital (to Risk Weighted Assets) 70,351 10.0 % 31,698 4.5 % 45,786 6.5 % Tier 1 Capital (to Risk Weighted Assets) 70,351 10.0 % 42,264 6.0 % 56,352 8.0 % Total Capital (to Risk Weighted Assets) 76,614 10.9 % 56,352 8.0 % 70,440 10.0 %

Common Stock (Tables)

Common Stock (Tables)	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of Compensation Expense and Related Tax Benefits for Restricted Stock Awards Recognized	The following table presents compensation expense and related tax benefits for restricted stock awards recognized on the consolidated statement of income. (Dollars in thousands) 2016 2015 2014 Compensation expense $ 53 $ 28 $ — Tax benefit (18 ) (10 ) — Net income effect $ 35 $ 18 $ —
Schedule of Non-Vested Restricted Stock	The following table presents information regarding the non-vested restricted stock for the year ended December 31, 2016. Shares Weighted- Non-vested at January 1, 2016 8,100 $ 16.13 Vested (2,115 ) 16.10 Cancelled (470 ) 16.09 Granted 7,540 18.77 Non-vested at December 31, 2016 13,055 17.66

Parent Company Statements (Tabl

Parent Company Statements (Tables)	12 Months Ended
	Dec. 31, 2016
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Condensed Balance Sheets	CONDENSED BALANCE SHEETS December 31, (Dollars in thousands) 2016 2015 ASSETS Cash and cash equivalents $ 780 $ 564 Equity investments 545 626 Investment in subsidiaries 77,029 76,334 Other assets 40 14 Total assets $ 78,394 $ 77,538 LIABILITIES AND SHAREHOLDERS’ EQUITY Subordinated debt $ 7,414 $ 7,414 Other liabilities 513 56 Shareholders’ equity 70,467 70,068 Total liabilities and shareholders’ equity $ 78,394 $ 77,538
Condensed Statements of Income and Comprehensive Income	CONDENSED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME For Years Ended December 31, (Dollars in thousands) 2016 2015 2014 Income Dividends from subsidiaries $ 2,871 $ 5,662 $ 2,325 Other income 33 19 — Total Income 2,904 5,681 2,325 Expense Other expenses (606 ) (695 ) (716 ) Total Expense (606 ) (695 ) (716 ) Income before income tax and equity in undistributed earnings (loss) of subsidiaries 2,298 4,986 1,609 Equity in undistributed earnings of subsidiaries 5,311 1,346 4,012 Income before income tax 7,609 6,332 5,621 Income tax benefit 195 196 80 Net income 7,804 6,528 5,701 Series B preferred stock dividends and redemption premium — 473 350 Series C preferred stock dividends — 17 — Net income available to common shareholders $ 7,804 $ 6,038 $ 5,351 Comprehensive income $ 3,139 $ 6,827 $ 8,086
Condensed Statement of Cash Flows	CONDENSED STATEMENTS OF CASH FLOWS For Years Ended December 31, (Dollars in thousands) 2016 2015 2014 CASH FLOWS FROM OPERATING ACTIVITIES Net income $ 7,804 $ 6,528 $ 5,701 Equity in undistributed earnings of subsidiaries (5,311 ) (1,346 ) (4,012 ) Decrease (increase) in other assets 59 (14 ) 8 Increase (decrease) in other liabilities 457 (665 ) 292 Net cash provided by operating activities 3,009 4,503 1,989 CASH FLOWS FROM INVESTING ACTIVITIES Net cash paid for acquisition — (2,949 ) — Net cash used in investing activities — (2,949 ) — CASH FLOWS FROM FINANCING ACTIVITIES Dividends paid (2,875 ) (2,175 ) (1,925 ) Series B preferred stock redemption premium — (100 ) — Series B preferred stock redemption — (5,000 ) — Series C preferred stock redemption — (1,750 ) — Employee Stock Purchase Plan 82 66 53 Deferred financing fees paid for subordinated debt issuance — (85 ) — Subordinated debt issuance — 7,500 — Net cash used in financing activities (2,793 ) (1,544 ) (1,872 ) Net increase in cash and cash equivalents 216 10 117 Cash and cash equivalents, beginning of year 564 554 437 Cash and cash equivalents, end of year $ 780 $ 564 $ 554

Summary of Quarterly Consolid54

Summary of Quarterly Consolidated Financial Data (Tables)	12 Months Ended
	Dec. 31, 2016
Parent Company [Member]
Summary of Quarterly Consolidated Financial Data (Unaudited) (Tables)	The following table presents summarized quarterly financial data for 2016 and 2015. 2016 Quarter Ended (Dollars in thousands, except per share data) March 31 June 30 September 30 December 31 Interest Income $ 9,697 $ 9,859 $ 10,125 $ 10,531 Interest Expense 1,282 1,316 1,367 1,402 Net Interest Income 8,415 8,543 8,758 9,129 Provision for Loan and Lease Losses 340 395 585 550 Net Interest Income After Provision for Loan Losses 8,075 8,148 8,173 8,579 Noninterest Income 1,232 1,398 1,419 1,875 Noninterest Expense 6,982 6,931 7,165 7,740 Income Before Provision for Income Taxes 2,325 2,615 2,427 2,714 Provision for Income Taxes 520 593 526 638 Net Income Available to Common Shareholders $ 1,805 $ 2,022 $ 1,901 $ 2,076 Per Share Data: Basic Earnings Per Common Share $ 0.43 $ 0.48 $ 0.45 $ 0.49 Cash Dividends Declared 0.22 0.12 0.12 0.22 2015 Quarter Ended (Dollars in thousands, except per share data) March 31 June 30 September 30 December 31 Interest Income $ 8,158 $ 9,644 $ 9,339 $ 9,349 Interest Expense 1,120 1,158 1,150 1,179 Net Interest Income 7,038 8,486 8,189 8,170 Provision for Loan and Lease Losses 300 300 265 200 Net Interest Income After Provision for Loan Losses 6,738 8,186 7,924 7,970 Noninterest Income 949 1,093 1,085 960 Noninterest Expense 6,640 6,642 6,569 6,882 Income Before Provision for Income Taxes 1,047 2,637 2,440 2,048 Provision for Income Taxes 84 593 546 421 Net Income 963 2,044 1,894 1,627 Series B Preferred Stock Dividends and Redemption Premium 87 88 88 210 Series C Preferred Stock Dividends — 4 4 9 Net Income Available to Common Shareholders $ 876 $ 1,952 $ 1,802 $ 1,408 Per Share Data: Basic Earnings Per Common Share $ 0.23 $ 0.46 $ 0.43 $ 0.35 Cash Dividends Declared 0.10 0.10 0.12 0.12

Earnings per Common Share (Tabl

Earnings per Common Share (Tables)	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Basic Earnings (Loss) Per Share	The computations of basic earnings per common share follow: (Dollars in thousands, except per share data) Three Months Six Months 2017 2016 2017 2016 Net income $ 2,345 $ 2,022 $ 4,339 $ 3,827 Weighted average common shares outstanding 4,234,291 4,227,992 4,234,525 4,227,362 Basic earnings per common share $ 0.55 $ 0.48 $ 1.02 $ 0.91

Basis of Presentation (Narrativ

Basis of Presentation (Narrative) (Detail)	12 Months Ended
	Dec. 31, 2016Segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of reportable segments	1

Nature of Business (Narrative)

Nature of Business (Narrative) (Detail)	Dec. 31, 2016Store
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of offices	21

Summary of Significant Accoun58

Summary of Significant Accounting Policies (Narrative) (Detail) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net gain on sales of investment securities	$ 12,000	$ 213,000	$ 20,000	$ 213,000	$ 1,046,000	$ 325,000	$ 168,000
Held-to-maturity Securities	71,096,000		71,096,000		0	0
Mortgage banking income	225,000	246,000	416,000	432,000	922,000	456,000	313,000
Other securities	64,000	$ 78,000	107,000	$ 172,000	304,000	382,000	155,000
Residential real estate held in other real estate owned					57,000	358,000
Foreclosure proceedings in process	$ 140,000		$ 140,000		426,000	0
Mortgage servicing rights					144,000	174,000
Mortgage servicing rights, amortization					30,000	24,000	36,000
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures					321,000	365,000
Low Income Housing Tax Credit					$ 46,000	46,000	46,000
Core Deposit Intangible, Amortization Period					10 years
Goodwill, Impairment Loss					$ 0	$ 0	$ 0
Class of warrant or right, outstanding	0	0	0	0	0	0	0
Federal Home Loan Bank of Pittsburgh [Member]
Other securities					$ 135,000	$ 250,000
Restricted investments					2,443,000	4,266,000
Reserve for Off-balance Sheet Activities [Member]
Valuation Allowances and Reserves, Balance					$ 120,000	$ 94,500
Commercial Portfolio [Member]
Loan Terms					1 year
Loan To Value Ratio					80.00%
Maximum [Member]
Maturity of interest bearing time deposits with other financial institutions					1 year
Non-residential consumer loans charged off on contractual basis in event of bankruptcy, in period					120 days
Maximum [Member] | Building Assets [Member]
Property, Plant and Equipment, Useful Life					50 years
Maximum [Member] | Furniture, Fixtures, and Equipment [Member]
Property, Plant and Equipment, Useful Life					10 years
Maximum [Member] | Land Improvements [Member]
Property, Plant and Equipment, Useful Life					20 years
Maximum [Member] | Leasehold Improvements [Member]
Property, Plant and Equipment, Useful Life					30 years
Maximum [Member] | Home equity lines of credit [Member]
Loan Terms					20 years
Loan To Value Ratio					85.00%
Maximum [Member] | Home Equity Lines Of Credit [Member]
Loan Terms					5 years
Maximum [Member] | Residential Portfolio [Member]
Loan Terms					30 years
Loan To Value Ratio					100.00%
Loan To Value Ratio, Exposure After Private Mortgage Insurance					85.00%
Minimum [Member] | Building Assets [Member]
Property, Plant and Equipment, Useful Life					5 years
Minimum [Member] | Furniture, Fixtures, and Equipment [Member]
Property, Plant and Equipment, Useful Life					3 years
Minimum [Member] | Land Improvements [Member]
Property, Plant and Equipment, Useful Life					10 years
Minimum [Member] | Leasehold Improvements [Member]
Property, Plant and Equipment, Useful Life					10 years

Summary of Significant Accoun59

Summary of Significant Accounting Policies (Basic Earnings (Loss) Per Share) (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended									6 Months Ended		12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income	$ 2,345			$ 2,022		$ 1,627	$ 1,894	$ 2,044	$ 963	$ 4,339	$ 3,827	$ 7,804	$ 6,528	$ 5,701
NET INCOME AVAILABLE TO COMMON SHAREHOLDERS		$ 2,076	$ 1,901	$ 2,022	$ 1,805	$ 1,408	$ 1,802	$ 1,952	$ 876			$ 7,804	$ 6,038	$ 5,351
Weighted average common shares outstanding	4,234,291			4,227,992						4,234,525	4,227,362	4,229,284	4,106,548	3,495,705
Basic earnings per common share	$ 0.55	$ 0.49	$ 0.45	$ 0.48	$ 0.43	$ 0.35	$ 0.43	$ 0.46	$ 0.23	$ 1.02	$ 0.91	$ 1.85	$ 1.47	$ 1.53
Series B Preferred Stock [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Dividends on preferred stock													$ 373	$ 350
Preferred stock redemption premium													100
Series C Preferred Stock [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Dividends on preferred stock						$ 9	$ 4	$ 4					$ 17

Mergers and Acquisitions (Narra

Mergers and Acquisitions (Narrative) (Detail) - USD ($)	Mar. 01, 2015	Feb. 27, 2015	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill			$ 3,918,000		$ 3,918,000				$ 3,918,000		$ 3,918,000	$ 3,918,000	$ 3,918,000
Net Income (Loss) Attributable to Parent			$ 2,345,000	$ 2,022,000	$ 1,627,000	$ 1,894,000	$ 2,044,000	$ 963,000	$ 4,339,000	$ 3,827,000		$ 7,804,000	6,528,000	$ 5,701,000
Series C Preferred Stock [Member]
Business Acquisition [Line Items]
Preferred Stock, Shares Issued	1,750
Preferred Stock, Liquidation Preference Per Share	$ 1,000
Phoenix Bancorp Inc. [Member]
Business Acquisition [Line Items]
Ratio of conversion of acquiree's shares to entity's shares	3.167%
Per share price	$ 51.60	$ 15.60
Shares Of Acquirer Ratio Of Common Stock	0.414%
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares	723,851
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	$ 11,292,000
Payments to Acquire Businesses, Gross	2,949,000	$ 2,949,000
Business Combination, Consideration Transferred	$ 14,241,000
Preferred Stock, Shares Issued	1,750
Goodwill	$ 2,902,000
Business Combination, Acquired Receivables, Fair Value	112,816,000
Pro Forma Earnings													5,811,000	$ 5,259,000
Revenues											4,244,000
Net Income (Loss) Attributable to Parent											$ 747,000
Phoenix Bancorp Inc. [Member] | Acquisition-related Costs [Member]
Business Acquisition [Line Items]
Pro Forma Earnings													$ 762,000
Phoenix Bancorp Inc. [Member] | Core Deposits [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired	$ 578,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	10 years
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	$ 86,000
Finite-Lived Intangible Assets, Amortization Expense, Year Two	75,000
Finite-Lived Intangible Assets, Amortization Expense, Year Three	65,000
Finite-Lived Intangible Assets, Amortization Expense, Year Four	54,000
Finite-Lived Intangible Assets, Amortization Expense, Year Five	44,000
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	$ 70,000
Phoenix Bancorp Inc. [Member] | Series C Preferred Stock [Member]
Business Acquisition [Line Items]
Preferred Stock, Shares Issued	1,750
Preferred Stock, Liquidation Preference Per Share	$ 1,000

Mergers and Acquisitions (Alloc

Mergers and Acquisitions (Allocation of the Purchase Price) (Detail) - USD ($)	Mar. 01, 2015	Feb. 27, 2015	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Assets acquired:
Goodwill			$ 3,918,000	$ 3,918,000	$ 3,918,000
Phoenix Bancorp Inc. [Member]
Assets acquired:
Cash and cash equivalents	$ 11,044,000
Investment securities	11,331,000
Loans	110,363,000
Goodwill	2,902,000
Core deposit and other intangibles	578,000
Other assets	7,489,000
Total assets acquired	143,707,000
Liabilities assumed:
Deposits	123,238,000
FHLB borrowings	3,570,000
Other liabilities	908,000
Total liabilities assumed	127,716,000
Equity acquired:
Preferred stock	1,750,000
Total equity acquired and liabilities assumed	129,466,000
Consideration paid	14,241,000
Cash paid	2,949,000	$ 2,949,000
Fair value of common stock issued, including replacement equity awards	$ 11,292,000

Mergers and Acquisitions (Estim

Mergers and Acquisitions (Estimated Fair Value of Assets Acquired) (Detail) - USD ($)	Mar. 01, 2015	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Net assets acquired:
Goodwill		$ 3,918,000	$ 3,918,000	$ 3,918,000
Phoenix Bancorp Inc. [Member]
Business Acquisition [Line Items]
Total purchase price	$ 14,241,000
Net assets acquired:
Cash and cash equivalents	11,044,000
Investment securities	11,331,000
Restricted stock	509,000
Loans	110,363,000
Bank owned life insurance	3,673,000
Premises and equipment	1,792,000
Deferred income taxes	503,000
Accrued interest receivable	388,000
Core deposit and other intangibles	578,000
Other assets	624,000
Deposits	(123,238,000)
FHLB borrowings	(3,570,000)
Accrued interest payable	(32,000)
Other liabilities	(876,000)
Preferred stock	(1,750,000)
Total net assets acquired	11,339,000
Goodwill	$ 2,902,000

Mergers and Acquisitions (Fair

Mergers and Acquisitions (Fair Value Adjustments) (Detail) - Phoenix Bancorp Inc. [Member]	Mar. 01, 2015USD ($)
Business Acquisition [Line Items]
Business Combination, Acquired Receivables, Fair Value	$ 112,816,000
Market rate adjustment	270,000
Credit fair value adjustment on pools of homogeneous loans	(1,461,000)
Credit fair value adjustment on impaired loans	(1,262,000)
Fair value of purchased loans	$ 110,363,000

Mergers and Acquisitions (Fai64

Mergers and Acquisitions (Fair Value of Loans Acquired) (Detail) - Phoenix Bancorp Inc. [Member] $ in Thousands	Mar. 01, 2015USD ($)
Business Acquisition [Line Items]
Contractually required principal and interest at acquisition	$ 3,548
Contractual cash flows not expected to be collected (nonaccretable discount)	(804)
Expected cash flows at acquisition	2,744
Interest component of expected cash flows (accretable discount)	(458)
Fair value of acquired loans	$ 2,286

Mergers and Acquisitions (Unaud

Mergers and Acquisitions (Unaudited Pro Forma Information) (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended									6 Months Ended		12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Net interest income after loan loss provision	$ 9,310	$ 8,579	$ 8,173	$ 8,138	$ 8,075	$ 7,970	$ 7,924	$ 8,186	$ 6,738	$ 18,360	$ 16,213	$ 32,975	$ 30,818	$ 24,583
Noninterest Income	1,362	1,875	1,419	1,398	1,232	960	1,085	1,093	949	2,798	2,630	5,924	4,113	3,284
Noninterest expense	$ 7,558	$ 7,740	$ 7,165	$ 6,921	$ 6,982	$ 6,882	$ 6,569	$ 6,642	$ 6,640	$ 15,360	$ 13,903	$ 28,818	26,759	20,704
Phoenix Bancorp Inc. [Member]
Business Acquisition [Line Items]
Net interest income after loan loss provision													31,454	29,745
Noninterest Income													4,152	4,131
Noninterest expense													27,817	26,846
Net income available to common shareholders													$ 5,811	$ 5,259
Net income per common share													$ 1.38	$ 1.25

Accumulated Other Comprehensi66

Accumulated Other Comprehensive Loss (Components of Accumulated Other Comprehensive Loss, Net of Taxes) (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Unrealized Loss on Securities	$ (1,073)	$ (2,919)	$ 1,565
Defined Benefit Plans	62	66	247
Accumulated Other Comprehensive Loss	$ (1,011)	$ (2,853)	$ 1,812

Investment Securities (Unrealiz

Investment Securities (Unrealized Gain (Loss) on Investments) (Detail) - USD ($)	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Investments [Line Items]
Available-for-sale securities, Amortized Cost	$ 112,979,000	$ 138,048,000	$ 133,350,000
Available-for-sale securities, Unrealized Gains	93,000	142,000	2,774,000
Available-for-sale securities, Unrealized Losses	1,719,000	4,565,000	403,000
Available for sale Securities, Fair Value	111,353,000	133,625,000	135,721,000
Held-to-maturity securities, Amortized Cost	71,096,000	0	0
Held-to-maturity securities, Unrealized Gains	216,000
Held-to-maturity securities, Unrealized Losses	113,000
Held-to-maturity securities, Fair Value	71,199,000	0
Available-for-sale securities and Held-to-maturity securities, Amortized Cost	184,075,000
Available-for-sale securities and Held-to-maturity securities, Unrealized Gains	309,000
Available-for-sale securities and Held-to-maturity securities, Unrealized Losses	1,832,000
Available-for-sale securities and Held-to-maturity securities, Fair Value	182,552,000
U.S. Treasury and U.S. government agencies [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, Amortized Cost	42,629,000	48,520,000	26,316,000
Available-for-sale securities, Unrealized Gains		34,000	729,000
Available-for-sale securities, Unrealized Losses	858,000	1,542,000	55,000
Available for sale Securities, Fair Value	41,771,000	47,012,000	26,990,000
Held-to-maturity securities, Amortized Cost	10,984,000
Held-to-maturity securities, Unrealized Gains	24,000
Held-to-maturity securities, Unrealized Losses	5,000
Held-to-maturity securities, Fair Value	11,003,000
Mortgage-backed U.S. Government Agencies [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, Amortized Cost	28,543,000	26,181,000	38,983,000
Available-for-sale securities, Unrealized Gains	3,000	17,000	49,000
Available-for-sale securities, Unrealized Losses	307,000	579,000	228,000
Available for sale Securities, Fair Value	28,239,000	25,619,000	38,804,000
Held-to-maturity securities, Amortized Cost	51,248,000
Held-to-maturity securities, Unrealized Gains	72,000
Held-to-maturity securities, Unrealized Losses	99,000
Held-to-maturity securities, Fair Value	51,221,000
State and political subdivision obligations [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, Amortized Cost	39,539,000	61,079,000	64,780,000
Available-for-sale securities, Unrealized Gains	70,000	91,000	1,914,000
Available-for-sale securities, Unrealized Losses	514,000	2,332,000	77,000
Available for sale Securities, Fair Value	39,095,000	58,838,000	66,617,000
Held-to-maturity securities, Amortized Cost	8,864,000
Held-to-maturity securities, Unrealized Gains	120,000
Held-to-maturity securities, Unrealized Losses	9,000
Held-to-maturity securities, Fair Value	8,975,000
Corporate debt securities [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, Amortized Cost	1,100,000	1,100,000	2,000,000
Available-for-sale securities, Unrealized Gains	5,000		80,000
Available-for-sale securities, Unrealized Losses			10,000
Available for sale Securities, Fair Value	1,105,000	1,100,000	2,070,000
Corporate debt securities [Member] | Scenario, Previously Reported [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, Amortized Cost		1,000,000
Available for sale Securities, Fair Value		1,000,000
Equity Securities [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, Amortized Cost	1,168,000	1,168,000	1,271,000
Available-for-sale securities, Unrealized Gains	15,000		2,000
Available-for-sale securities, Unrealized Losses	40,000	112,000	33,000
Available for sale Securities, Fair Value	$ 1,143,000	1,056,000	$ 1,240,000
Equity Securities [Member] | Scenario, Previously Reported [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, Amortized Cost		1,268,000
Available-for-sale securities, Unrealized Losses		112,000
Available for sale Securities, Fair Value		$ 1,156,000

Investment Securities (Narrativ

Investment Securities (Narrative) (Detail)	3 Months Ended	6 Months Ended		12 Months Ended
	Jun. 30, 2017USD ($)Security	Jun. 30, 2017USD ($)Security	Jun. 30, 2016USD ($)	Dec. 31, 2016USD ($)Security	Dec. 31, 2015USD ($)Security	Dec. 31, 2014USD ($)
Schedule of Investments [Line Items]
Available-for-sale Securities Pledged as Collateral	$ 126,032,000	$ 126,032,000		$ 131,469,000	$ 130,298,000
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | Security	97	97		151	47
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ 1,719,000	$ 1,719,000		$ 4,565,000	$ 403,000
Available-for-sale, Securities in Unrealized Loss Positions, Depreciation Percentage				3.82%	1.19%
Available-for-sale Securities, Gross Realized Gains	77,000	200,000	$ 450,000	$ 1,927,000	$ 325,000	$ 168,000
Available-for-sale Securities, Gross Realized Losses	(65,000)	(180,000)	$ (237,000)	$ 881,000	0	$ 0
Number of debt securities sold for gross realized gains | Security				102
Number of debt securities sold for gross realized losses | Security				56
Held to maturity securities	$ 71,096,000	$ 71,096,000		$ 0	$ 0
Debt Securities [Member]
Schedule of Investments [Line Items]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | Security				149	45
Equity Securities [Member]
Schedule of Investments [Line Items]
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | Security	1	1		2	2
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss	$ 40,000	$ 40,000		$ 112,000	$ 33,000

Investment Securities (Schedule

Investment Securities (Schedule of Fair Value and Unrealized Loss on Investments in a Continuous Unrealized Loss Position) (Detail) $ in Thousands	Jun. 30, 2017USD ($)Security	Dec. 31, 2016USD ($)Security	Dec. 31, 2015USD ($)Security
Schedule of Investments [Line Items]
Available-for-sale securities, Less than 12 Months: Number of Securities | Security	87	149	29
Available-for-sale securities, Less than 12 Months: Fair Value	$ 89,664	$ 118,601	$ 24,049
Available-for-sale securities, Less than 12 Months: Unrealized Losses	$ 1,524	$ 4,453	$ 209
Available-for-sale securities, 12 Months or More: Number of Securities | Security	10	2	18
Available-for-sale securities, 12 Months or More: Fair Value	$ 7,624	$ 1,056	$ 9,911
Available-for-sale securities, 12 Months or More: Unrealized Losses	$ 195	$ 112	$ 194
Available-for-sale securities, Total: Number of Securities | Security	97	151	47
Available-for-sale securities, Total: Fair Value	$ 97,288	$ 119,657	$ 33,960
Available-for-sale securities, Total: Unrealized Losses	$ 1,719	$ 4,565	$ 403
Held-to-maturity securities, Less than 12 Months: Number of Securities | Security	19
Held-to-maturity securities, Less than 12 Months: Fair Value	$ 29,406
Held-to-maturity securities, Less than 12 Months: Unrealized Losses	$ 113
Held-to-maturity securities, 12 Months or More: Number of Securities | Security	0
Held-to-maturity securities, Total: Number of Securities | Security	19
Held-to-maturity securities, Total: Fair Value	$ 29,406
Held-to-maturity securities, Total: Unrealized Losses	$ 113
Available-for-sale securities and Held-to-maturity securities, Less than 12 Months: Number of Securities | Security	106
Available for Sale Securities and Held to Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value	$ 119,070
Available-for-sale securities and Held-to-maturity securities, Less than 12 Months: Unrealized Losses	$ 1,637
Available-for-sale securities and Held-to-maturity securities,, 12 Months or More: Number of Securities | Security	10
Available-for-sale securities and Held-to-maturity securities, 12 Months or More: Fair Value	$ 7,624
Available-for-sale securities and Held-to-maturity securities, 12 Months or More: Unrealized Losses	$ 195
Available-for-sale securities and Held-to-maturity securities, Total: Number of Securities | Security	116
Available-for-sale securities and Held-to-maturity securities, Total: Fair Value	$ 126,694
Available-for-sale securities and Held-to-maturity securities, Total: Unrealized Losses	$ 1,832
U.S. Treasury and U.S. government agencies [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, Less than 12 Months: Number of Securities | Security	21	23	6
Available-for-sale securities, Less than 12 Months: Fair Value	$ 39,077	$ 43,698	$ 6,259
Available-for-sale securities, Less than 12 Months: Unrealized Losses	$ 852	$ 1,542	$ 43
Available-for-sale securities, 12 Months or More: Number of Securities | Security	1	0	2
Available-for-sale securities, 12 Months or More: Fair Value	$ 2,694		$ 1,383
Available-for-sale securities, 12 Months or More: Unrealized Losses	$ 6		$ 12
Available-for-sale securities, Total: Number of Securities | Security	22	23	8
Available-for-sale securities, Total: Fair Value	$ 41,771	$ 43,698	$ 7,642
Available-for-sale securities, Total: Unrealized Losses	$ 858	$ 1,542	$ 55
Held-to-maturity securities, Less than 12 Months: Number of Securities | Security	2
Held-to-maturity securities, Less than 12 Months: Fair Value	$ 4,991
Held-to-maturity securities, Less than 12 Months: Unrealized Losses	$ 5
Held-to-maturity securities, 12 Months or More: Number of Securities | Security	0
Held-to-maturity securities, Total: Number of Securities | Security	2
Held-to-maturity securities, Total: Fair Value	$ 4,991
Held-to-maturity securities, Total: Unrealized Losses	$ 5
Mortgage-backed U.S. Government Agencies [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, Less than 12 Months: Number of Securities | Security	18	18	13
Available-for-sale securities, Less than 12 Months: Fair Value	$ 26,466	$ 24,321	$ 12,759
Available-for-sale securities, Less than 12 Months: Unrealized Losses	$ 291	$ 579	$ 124
Available-for-sale securities, 12 Months or More: Number of Securities | Security	1	0	11
Available-for-sale securities, 12 Months or More: Fair Value	$ 535		$ 6,282
Available-for-sale securities, 12 Months or More: Unrealized Losses	$ 16		$ 104
Available-for-sale securities, Total: Number of Securities | Security	19	18	24
Available-for-sale securities, Total: Fair Value	$ 27,001	$ 24,321	$ 19,041
Available-for-sale securities, Total: Unrealized Losses	$ 307	$ 579	$ 228
Held-to-maturity securities, Less than 12 Months: Number of Securities | Security	14
Held-to-maturity securities, Less than 12 Months: Fair Value	$ 22,879
Held-to-maturity securities, Less than 12 Months: Unrealized Losses	$ 99
Held-to-maturity securities, 12 Months or More: Number of Securities | Security	0
Held-to-maturity securities, Total: Number of Securities | Security	14
Held-to-maturity securities, Total: Fair Value	$ 22,879
Held-to-maturity securities, Total: Unrealized Losses	$ 99
State and political subdivision obligations [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, Less than 12 Months: Number of Securities | Security	48	108	9
Available-for-sale securities, Less than 12 Months: Fair Value	$ 24,121	$ 50,582	$ 4,041
Available-for-sale securities, Less than 12 Months: Unrealized Losses	$ 381	$ 2,332	$ 32
Available-for-sale securities, 12 Months or More: Number of Securities | Security	7	0	3
Available-for-sale securities, 12 Months or More: Fair Value	$ 3,845		$ 1,631
Available-for-sale securities, 12 Months or More: Unrealized Losses	$ 133		$ 45
Available-for-sale securities, Total: Number of Securities | Security	55	108	12
Available-for-sale securities, Total: Fair Value	$ 27,966	$ 50,582	$ 5,672
Available-for-sale securities, Total: Unrealized Losses	$ 514	$ 2,332	$ 77
Held-to-maturity securities, Less than 12 Months: Number of Securities | Security	3
Held-to-maturity securities, Less than 12 Months: Fair Value	$ 1,536
Held-to-maturity securities, Less than 12 Months: Unrealized Losses	$ 9
Held-to-maturity securities, 12 Months or More: Number of Securities | Security	0
Held-to-maturity securities, Total: Number of Securities | Security	3
Held-to-maturity securities, Total: Fair Value	$ 1,536
Held-to-maturity securities, Total: Unrealized Losses	$ 9
Equity Securities [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, Less than 12 Months: Number of Securities | Security	0	0	0
Available-for-sale securities, 12 Months or More: Number of Securities | Security	1	2	2
Available-for-sale securities, 12 Months or More: Fair Value	$ 550	$ 1,056	$ 615
Available-for-sale securities, 12 Months or More: Unrealized Losses	$ 40	$ 112	$ 33
Available-for-sale securities, Total: Number of Securities | Security	1	2	2
Available-for-sale securities, Total: Fair Value	$ 550	$ 1,056	$ 615
Available-for-sale securities, Total: Unrealized Losses	$ 40	$ 112	$ 33
Corporate debt securities [Member]
Schedule of Investments [Line Items]
Available-for-sale securities, Less than 12 Months: Number of Securities | Security			1
Available-for-sale securities, Less than 12 Months: Fair Value			$ 990
Available-for-sale securities, Less than 12 Months: Unrealized Losses			$ 10
Available-for-sale securities, 12 Months or More: Number of Securities | Security			0
Available-for-sale securities, Total: Number of Securities | Security			1
Available-for-sale securities, Total: Fair Value			$ 990
Available-for-sale securities, Total: Unrealized Losses			$ 10

Investment Securities (Investme

Investment Securities (Investments Classified by Contractual Maturity Date) (Detail) - USD ($)	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Investments [Line Items]
Available for sale Securities, Amortized Cost, Due in 1 year or less	$ 1,293,000	$ 1,293,000
Available for sale Securities, Amortized Cost, Due after 1 year but within 5 years	20,311,000	19,656,000
Available for sale Securities, Amortized Cost, Due after 5 years but within 10 years	47,618,000	66,084,000
Available for sale Securities, Amortized Cost, Due after 10 years	14,046,000	23,566,000
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis, Total	83,268,000	110,599,000
Equity Securities, Amortized Cost	1,168,000	1,268,000
Available-for-sale securities, Amortized Cost	112,979,000	138,048,000	$ 133,350,000
Available for sale Securities, Fair Value, Due in 1 year or less	1,292,000	1,305,000
Available for sale Securities, Fair Value, Due after 1 year but within 5 years	20,178,000	19,471,000
Available for sale Securities, Fair Value, Due after 5 years but within 10 years	46,801,000	63,895,000
Available for sale Securities, Fair Value, Due after 10 years	13,700,000	22,179,000
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Fair Value, Total	81,971,000	106,850,000
Equity Securities, Fair Value	1,143,000	1,156,000
Available for sale Securities, Fair Value	111,353,000	133,625,000	135,721,000
Held-to-maturity, Due after 1 year through 5 years, Amortized Cost	14,486,000
Held-to-maturity, Due after 5 years through 10 years, Amortized Cost	5,362,000
Held-to-maturity Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis	19,848,000
Held-to-maturity securities, Amortized Cost	71,096,000	0	$ 0
Held-to-maturity, Due after 1 year through 5, Fair Value	14,546,000
Held-to-maturity, Due after 5 years through 10 years, Fair Value	5,432,000
Held-to-maturity Securities, Debt Maturities, Single Maturity Date, Fair Value	19,978,000
Held-to-maturity, Fair Value	71,199,000	0
Mortgage-backed securities [Member]
Schedule of Investments [Line Items]
Available for sale Securities without a Single Maturity Date, Amortized Cost	28,543,000	26,181,000
Available for sale securities without a Single Maturity Date, Fair Value	28,239,000	$ 25,619,000
Held-to-maturity without Single Maturity Date, Amortized Cost	51,248,000
Held-to-maturity without Single Maturity Date, Fair Value	$ 51,221,000

Loans and Allowance for Loan 71

Loans and Allowance for Loan and Lease Losses (Narrative) (Detail)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017USD ($)Loans	Jun. 30, 2016USD ($)Loans	Jun. 30, 2017USD ($)Loans	Jun. 30, 2016USD ($)Loans	Dec. 31, 2016USD ($)Loans	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)Loans	Dec. 31, 2013USD ($)Loans	Dec. 31, 2009Loans	Dec. 31, 2008Loans	Mar. 29, 2017USD ($)	Mar. 31, 2016USD ($)
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable Deferred Fees And Costs	$ 435,000		$ 435,000		$ 196,000	$ 178,000
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans					666,000	778,000	$ 798,000
Loans and Leases Receivable, Impaired, Commitment to Lend					0
Financing Receivable, Modifications, Recorded Investment	$ 3,030,000		3,030,000		3,515,000	2,805,000
Charge-offs associated with troubled debt restructured loans			$ 0	$ 0	$ 0	0
Number of troubled debt restructured loans | Loans	0	0	0	0	0
Loans to certain executive officers, directors, and their related interests					$ 17,594,000	10,657,000
Loans to certain executive officers, directors, and their related interests, new loans and advances					14,479,000
Loans to certain executive officers, directors, and their related interests, Repayments					7,542,000
Contractual payment of principal or interest past due period for discontinuing accrual of interest			90 days
Financing Receivable, Allowance for Credit Losses	$ 7,713,000	$ 6,912,000	$ 7,713,000	$ 6,912,000	7,183,000	6,168,000	$ 6,716,000	$ 6,317,000			$ 7,620,000	$ 6,439,000
Non-residential loans and lease charged off period			120 days
Number of additional troubled debt restructured loans | Loans	0	0	0	0
Other Real Estate	$ 0		$ 0		57,000
Number of consumer mortgage loans foreclosure proceedings in process | Loans			3
Loans for which formal foreclosure proceedings are in process	140,000		$ 140,000		$ 426,000	0
Under Forbearance Agreement 2016 Period [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Number of forbearance agreements negotiated | Loans					3		1	2	8	1
Under Forbearance Agreement 2015 Period [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Number of forbearance agreements negotiated | Loans							1	2	9	1
Accruing [Member] | Five Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Recorded Investment					$ 877,000
Accruing [Member] | Four Borrowers [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Recorded Investment						459,000
Accruing [Member] | One Loan [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Recorded Investment	503,000		503,000
Nonaccruing [Member] | Ten Loans With Four Relationships [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Recorded Investment	2,473,000		2,473,000		2,638,000
Nonaccruing [Member] | Two Large Relationships [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Recorded Investment	2,057,000		$ 2,057,000		2,170,000
Nonaccruing [Member] | Nine Loans Four Related Borrowers [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Recorded Investment						2,346,000
Nonaccruing [Member] | One of Four Relationships Borrowers [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Recorded Investment						1,370,000
Residential Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Maximum loan maturity period			30 years
Residential Mortgage [Member] | Residential Portfolio [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Recorded Investment	623,000		$ 623,000		639,000	555,000
Financing Receivable, Allowance for Credit Losses	539,000	$ 521,000	539,000	$ 521,000	541,000	534,000	$ 450,000	$ 581,000			532,000	516,000
Residential Mortgage [Member] | Accruing [Member] | Four Unrelated Borrowers [Member] | Residential Portfolio [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Recorded Investment					571,000
Residential Mortgage [Member] | Accruing [Member] | Three of Four Unrelated Borrowers [Member] | Consumer Portfolio [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Recorded Investment						64,000
Residential Mortgage [Member] | Accruing [Member] | Four Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Recorded Investment	557,000		$ 557,000
Residential Mortgage [Member] | Minimum [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan-to-value ratio			100.00%
Commercial Real Estate [Member] | Commercial Portfolio [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Recorded Investment	2,407,000		$ 2,407,000		2,871,000	2,235,000
Financing Receivable, Allowance for Credit Losses	4,981,000	4,241,000	$ 4,981,000	4,241,000	4,323,000	3,552,000	3,925,000	4,006,000			4,715,000	3,777,000
Commercial Real Estate [Member] | Accruing [Member] | Other Borrower [Member] | Commercial Portfolio [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Recorded Investment					306,000	395,000
Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Maximum term on non-mortgage lines of credit			1 year
Commercial and Industrial [Member] | Commercial Portfolio [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Recorded Investment					5,000	15,000
Financing Receivable, Allowance for Credit Losses	$ 1,628,000	1,372,000	$ 1,628,000	1,372,000	1,580,000	1,393,000	1,393,000	1,187,000			1,630,000	1,427,000
Commercial and Industrial [Member] | LTV Less than 80 Percent [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan-to-value ratio			80.00%
Private Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loan-to-value ratio			85.00%
Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Maximum loan maturity period			20 years
Percentage of appraised Value of property securing loan	85.00%		85.00%
Mortgage Lines Of Credit Period			5 years
Financing Receivable, Allowance for Credit Losses	$ 404,000	$ 325,000	$ 404,000	$ 325,000	379,000	$ 317,000	$ 653,000	$ 441,000			$ 364,000	$ 303,000
Unfunded Lending Commitments [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Allowance for Credit Losses	$ 127,000		$ 127,000		$ 120,000

Loans and Allowance for Loan 72

Loans and Allowance for Loan and Lease Losses (Classes Of The Loan Portfolio Summarized By The Aggregate Risk Rating) (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	$ 862,307	$ 813,924	$ 769,153	$ 736,513	$ 571,533
Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	38,671	37,608	34,579	33,411	28,506
Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	844,846	799,937		722,905
Pass [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	38,154	37,242		32,928
Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	6,559	3,071		6,516
Special Mention [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	124	142		261
Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	10,902	10,916		9,770
Substandard [Member] | Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	393	224		222
Commercial Portfolio [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	181,368	172,518	160,278	160,261	119,010
Commercial Portfolio [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	482,141	446,524	410,786	369,464	297,357
Commercial Portfolio [Member] | Commercial Real Estate - Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	53,305	54,376	56,074	68,068	56,076
Commercial Portfolio [Member] | Pass [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	175,700	170,780		158,302
Commercial Portfolio [Member] | Pass [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	473,078	437,592		359,859
Commercial Portfolio [Member] | Pass [Member] | Commercial Real Estate - Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	52,543	52,888		65,665
Commercial Portfolio [Member] | Special Mention [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	4,385	937		1,289
Commercial Portfolio [Member] | Special Mention [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	1,757	1,683		2,088
Commercial Portfolio [Member] | Special Mention [Member] | Commercial Real Estate - Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	191	202		2,403
Commercial Portfolio [Member] | Substandard [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	1,283	801		670
Commercial Portfolio [Member] | Substandard [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	7,306	7,249		7,517
Commercial Portfolio [Member] | Substandard [Member] | Commercial Real Estate - Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	571	1,286
Finance Leases Portfolio [Member] | Lease Financing [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	307	425	565	727	1,121
Finance Leases Portfolio [Member] | Pass [Member] | Lease Financing [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	307	425		727
Residential Portfolio [Member] | Residential Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	102,637	99,457	103,822	100,665	66,442
Residential Portfolio [Member] | Pass [Member] | Residential Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	101,186	97,994		101,507
Residential Portfolio [Member] | Special Mention [Member] | Residential Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	102	107		475
Residential Portfolio [Member] | Substandard [Member] | Residential Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	1,349	1,356		1,361
Consumer Portfolio [Member] | Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	3,878	3,016	$ 3,049	3,917	$ 3,021
Consumer Portfolio [Member] | Pass [Member] | Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	$ 3,878	$ 3,016		$ 3,917

Loans and Allowance for Loan 73

Loans and Allowance for Loan and Lease Losses (Impaired Loans by Loan Portfolio Class) (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Recorded Investment	$ 327	$ 111	$ 115
Impaired Loans with No Allowance: Unpaid Principal Balance	369	129	137
Impaired Loans with Allowance: Recorded Investment		29
Impaired Loans with Allowance: Unpaid Principal Balance		49
Impaired Loans with Allowance: Related Allowance		1
Impaired Loans: Total Recorded Investment	327	140	115
Impaired Loans: Total Unpaid Principal Balance	369	178	137
Commercial Portfolio [Member] | Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Recorded Investment		4	14
Impaired Loans with No Allowance: Unpaid Principal Balance	18	9	49
Impaired Loans with Allowance: Recorded Investment		56	113
Impaired Loans with Allowance: Unpaid Principal Balance		62	128
Impaired Loans with Allowance: Related Allowance		6	51
Impaired Loans: Total Recorded Investment		60	127
Impaired Loans: Total Unpaid Principal Balance	18	71	177
Commercial Portfolio [Member] | Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Recorded Investment	900	726	1,023
Impaired Loans with No Allowance: Unpaid Principal Balance	1,390	1,792	2,020
Impaired Loans with Allowance: Recorded Investment	2,751	2,520	1,947
Impaired Loans with Allowance: Unpaid Principal Balance	2,915	2,646	1,981
Impaired Loans with Allowance: Related Allowance	893	711	429
Impaired Loans: Total Recorded Investment	4,224	4,088	3,901
Impaired Loans: Total Unpaid Principal Balance	4,878	5,280	4,001
Commercial Portfolio [Member] | Commercial Real Estate [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Recorded Investment	573	842	931
Impaired Loans with No Allowance: Unpaid Principal Balance	573	842	931
Commercial Portfolio [Member] | Commercial Real Estate - Construction [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Recorded Investment	331	618
Impaired Loans with No Allowance: Unpaid Principal Balance	334	618
Impaired Loans with Allowance: Recorded Investment	240	242
Impaired Loans with Allowance: Unpaid Principal Balance	242	242
Impaired Loans with Allowance: Related Allowance	70	72
Impaired Loans: Total Recorded Investment	571	860
Impaired Loans: Total Unpaid Principal Balance	576	860
Residential Portfolio [Member] | Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Recorded Investment	902	848	1,329
Impaired Loans with No Allowance: Unpaid Principal Balance	931	882	1,434
Impaired Loans with Allowance: Recorded Investment	66	68	32
Impaired Loans with Allowance: Unpaid Principal Balance	68	68	32
Impaired Loans with Allowance: Related Allowance	66	68	23
Impaired Loans: Total Recorded Investment	1,292	1,305	1,761
Impaired Loans: Total Unpaid Principal Balance	1,323	1,339	1,466
Residential Portfolio [Member] | Residential Mortgage [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Recorded Investment	324	389	400
Impaired Loans with No Allowance: Unpaid Principal Balance	$ 324	$ 389	$ 400

Loans and Allowance for Loan 74

Loans and Allowance for Loan and Lease Losses (Average Recorded Investment Of Impaired Loans And Related Interest Income By Loan Portfolio Class) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Average Recorded Investment	$ 90	$ 66	$ 101	$ 53	$ 75	$ 107	$ 29
Impaired Loans with No Allowance: Interest Income Recognized			2
Impaired Loans with Allowance: Average Recorded Investment		17		19	32		76
Impaired Financing Receivable, Average Recorded Investment, Total	90	83	101	72	107	107	105
Impaired Financing Receivable, Interest Income Recognized, Total			2			3
Commercial Portfolio [Member] | Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Average Recorded Investment	36	11	18	14	9	19	72
Impaired Loans with Allowance: Average Recorded Investment		59		61	59	123	93
Impaired Financing Receivable, Average Recorded Investment, Total	36	70	18	75	68	142	165
Impaired Financing Receivable, Interest Income Recognized, Total						205
Commercial Portfolio [Member] | Commercial and Industrial [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Interest Income Recognized						205
Commercial Portfolio [Member] | Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Average Recorded Investment	644	960	524	1,001	820	1,051	1,966
Impaired Loans with No Allowance: Interest Income Recognized			279			14	346
Impaired Loans with Allowance: Average Recorded Investment	2,792	2,201	2,660	1,851	2,177	1,721	6,823
Impaired Financing Receivable, Average Recorded Investment, Total	4,080	4,104	3,922	3,786	3,807	3,698	8,789
Impaired Financing Receivable, Interest Income Recognized, Total	110		389		164	364	346
Commercial Portfolio [Member] | Commercial Real Estate [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Average Recorded Investment	644	943	738	934	810	926
Impaired Loans with No Allowance: Interest Income Recognized	110		110		164	350
Commercial Portfolio [Member] | Commercial Real Estate - Construction [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Average Recorded Investment	473		313		124
Impaired Loans with Allowance: Average Recorded Investment	240		144		48
Impaired Financing Receivable, Average Recorded Investment, Total	713		457		172
Residential Portfolio [Member] | Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Average Recorded Investment	860	831	843	777	821	816	541
Impaired Loans with No Allowance: Interest Income Recognized	7	7	18	9	21	8
Impaired Loans with Allowance: Average Recorded Investment	66		40		14	25
Impaired Financing Receivable, Average Recorded Investment, Total	1,252	1,208	1,233	1,152	1,213	1,241	$ 541
Impaired Financing Receivable, Interest Income Recognized, Total	9	7	18	13	25	8
Residential Portfolio [Member] | Residential Mortgage [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Average Recorded Investment	326	$ 377	$ 350	375	378	400
Impaired Loans with No Allowance: Interest Income Recognized	$ 2			$ 4	$ 4
Consumer Portfolio [Member] | Home Equity [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Impaired [Line Items]
Impaired Loans with No Allowance: Interest Income Recognized						$ 3

Loans and Allowance for Loan 75

Loans and Allowance for Loan and Lease Losses (Nonaccrual Loans By Classes Of The Loan Portfolio) (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 5,218	$ 4,658	$ 4,418
Home Equity [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	327	140	115
Commercial Portfolio [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status		4	66
Commercial Portfolio [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	3,630	2,939	2,607
Commercial Portfolio [Member] | Commercial Real Estate - Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	571	860
Residential Portfolio [Member] | Residential Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 690	$ 715	$ 1,630

Loans and Allowance for Loan 76

Loans and Allowance for Loan and Lease Losses (Loan Portfolio Summarized By The Past Due Status) (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	$ 9,536	$ 3,524		$ 5,732
Financing Receivable, Recorded Investment, Current	852,771	810,400		730,781
Total Loans	862,307	813,924	$ 769,153	736,513	$ 571,533
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	57	59		55
Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	897	1,231	1,321	1,331
Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	1,457	1,220		1,197
Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	4,246	553		1,935
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	3,833	1,751		2,600
Home Equity [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	311	171		73
Financing Receivable, Recorded Investment, Current	38,360	37,437		33,338
Total Loans	38,671	37,608	34,579	33,411	28,506
Home Equity [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	13	33
Home Equity [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		13		50
Home Equity [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	298	125		23
Commercial Portfolio [Member] | Commercial and Industrial [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	4,184	180		325
Financing Receivable, Recorded Investment, Current	177,184	172,338		159,936
Total Loans	181,368	172,518	160,278	160,261	119,010
Commercial Portfolio [Member] | Commercial and Industrial [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	101	164		55
Commercial Portfolio [Member] | Commercial and Industrial [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	4,083	12		204
Commercial Portfolio [Member] | Commercial and Industrial [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		4		66
Commercial Portfolio [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	482,141	446,524	410,786	369,464	297,357
Commercial Portfolio [Member] | Commercial Real Estate [Member] | Excluded Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	2,795	1,479		2,275
Financing Receivable, Recorded Investment, Current	478,773	444,203		366,258
Total Loans	481,568	445,682		368,533
Commercial Portfolio [Member] | Commercial Real Estate [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	573	59		788
Financing Receivable, Recorded Investment, Current		783		143
Total Loans	573	842	951	931
Financing Receivable, Recorded Investment, 90 Days Past Due and Still Accruing	57	59		55
Commercial Portfolio [Member] | Commercial Real Estate [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Excluded Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	250	475		211
Commercial Portfolio [Member] | Commercial Real Estate [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	516			215
Commercial Portfolio [Member] | Commercial Real Estate [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Excluded Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	43			608
Commercial Portfolio [Member] | Commercial Real Estate [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due				518
Commercial Portfolio [Member] | Commercial Real Estate [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Excluded Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	2,502	1,004		1,456
Commercial Portfolio [Member] | Commercial Real Estate [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	57	59		55
Commercial Portfolio [Member] | Commercial Real Estate - Construction [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	942	488
Financing Receivable, Recorded Investment, Current	52,363	53,888		68,068
Total Loans	53,305	54,376	56,074	68,068	56,076
Commercial Portfolio [Member] | Commercial Real Estate - Construction [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	371
Commercial Portfolio [Member] | Commercial Real Estate - Construction [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	120	404
Commercial Portfolio [Member] | Commercial Real Estate - Construction [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	451	84
Finance Leases Portfolio [Member] | Lease Financing [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing Receivable, Recorded Investment, Current	307	425		727
Total Loans	307	425	565	727	1,121
Residential Portfolio [Member] | Residential Mortgage [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	102,637	99,457	103,822	100,665	66,442
Residential Portfolio [Member] | Residential Mortgage [Member] | Excluded Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	473	909		2,022
Financing Receivable, Recorded Investment, Current	101,840	98,159		98,243
Total Loans	102,313	99,068		100,265
Residential Portfolio [Member] | Residential Mortgage [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	258	238		234
Financing Receivable, Recorded Investment, Current	66	151		166
Total Loans	324	389	370	400
Residential Portfolio [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Residential Mortgage [Member] | Excluded Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	174	548		694
Residential Portfolio [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Residential Mortgage [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	32			12
Residential Portfolio [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Residential Mortgage [Member] | Excluded Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due		124		550
Residential Portfolio [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Residential Mortgage [Member] | Excluded Acquired with Credit Deterioration [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	299	237		778
Residential Portfolio [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Residential Mortgage [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due	226	238		222
Consumer Portfolio [Member] | Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due				15
Financing Receivable, Recorded Investment, Current	3,878	3,016		3,902
Total Loans	$ 3,878	$ 3,016	$ 3,049	3,917	$ 3,021
Consumer Portfolio [Member] | Financing Receivables, 30 to 59 Days Past Due [Member] | Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due				10
Consumer Portfolio [Member] | Financing Receivables, 60 to 89 Days Past Due [Member] | Consumer [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due				$ 5

Loans and Allowance for Loan 77

Loans and Allowance for Loan and Lease Losses (Allowance For Loan Losses And Recorded Investment In Financing Receivables) (Detail) - USD ($) $ in Thousands	3 Months Ended									6 Months Ended		12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning Balance	$ 7,620		$ 6,912	$ 6,439	$ 6,168				$ 6,716	$ 7,183	$ 6,168	$ 6,168	$ 6,716	$ 6,317
Charge-offs	(40)			(86)						(76)	(185)	(1,107)	(1,784)	(1,328)
Recoveries	33			164						381	194	252	171	110
Provisions	100	$ 550	585	395	340	$ 200	$ 265	$ 300	300	225	735	1,870	1,065	1,617
Allowance for Loan Losses, Ending Balance	7,713	7,183		6,912	6,439	6,168				7,713	6,912	7,183	6,168	6,716
Allowance for loan losses: Ending balance: individually evaluated for impairment	1,029	858		774		503				1,029	774	858	503	1,634
Allowance for loan losses: Ending balance: collectively evaluated for impairment	6,684	6,325		6,138		5,665				6,684	6,138	6,325	5,665	5,082
Loans receivables, Ending Balance	862,307	813,924		769,153		736,513				862,307	769,153	813,924	736,513	571,533
Loans receivables: Ending balance: individually evaluated for impairment	5,517	5,222		4,630		4,573				5,517	4,630	5,222	4,573	10,929
Loans Receivable: Ending balance: collectively evaluated for impairment	855,893	807,471		763,202		730,609				855,893	763,202	807,471	730,609	560,604
Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivables, Ending Balance	897	1,231		1,321		1,331				897	1,321	1,231	1,331
Home Equity [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning Balance	364		325	303	317				653	379	317	317	653	441
Charge-offs				(25)							(25)	(25)	(36)	(43)
Recoveries	5									5			29	1
Provisions	35			47						20	33	87	(329)	254
Allowance for Loan Losses, Ending Balance	404	379		325	303	317				404	325	379	317	653
Allowance for loan losses: Ending balance: individually evaluated for impairment		1		2							2	1		115
Allowance for loan losses: Ending balance: collectively evaluated for impairment	404	378		323		317				404	323	378	317	538
Loans receivables, Ending Balance	38,671	37,608		34,579		33,411				38,671	34,579	37,608	33,411	28,506
Loans receivables: Ending balance: individually evaluated for impairment	327	140		81		115				327	81	140	115	240
Loans Receivable: Ending balance: collectively evaluated for impairment	38,344	37,468		34,498		33,296				38,344	34,498	37,468	33,296	28,266
Commercial Portfolio [Member] | Commercial and Industrial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning Balance	1,630		1,372	1,427	1,393				1,393	1,580	1,393	1,393	1,393	1,187
Charge-offs										(12)		(820)	(130)	(62)
Recoveries	3			1						7	2	4	12	13
Provisions	(5)			(56)						53	(23)	1,003	118	255
Allowance for Loan Losses, Ending Balance	1,628	1,580		1,372	1,427	1,393				1,628	1,372	1,580	1,393	1,393
Allowance for loan losses: Ending balance: individually evaluated for impairment		6		3		51					3	6	51	137
Allowance for loan losses: Ending balance: collectively evaluated for impairment	1,628	1,574		1,369		1,342				1,628	1,369	1,574	1,342	1,256
Loans receivables, Ending Balance	181,368	172,518		160,278		160,261				181,368	160,278	172,518	160,261	119,010
Loans receivables: Ending balance: individually evaluated for impairment		60		68		127					68	60	127	618
Loans Receivable: Ending balance: collectively evaluated for impairment	181,368	172,458		160,210		160,134				181,368	160,210	172,458	160,134	118,392
Commercial Portfolio [Member] | Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning Balance	4,715		4,241	3,777	3,552				3,925	4,323	3,552	3,552	3,925	4,006
Charge-offs	(30)			(54)						(30)	(150)	(216)	(1,569)	(1,057)
Recoveries	22			136						361	161	211	75	13
Provisions	274			382						327	678	776	1,121	963
Allowance for Loan Losses, Ending Balance	4,981	4,323		4,241	3,777	3,552				4,981	4,241	4,323	3,552	3,925
Allowance for loan losses: Ending balance: individually evaluated for impairment	893	711		769		429				893	769	711	429	1,382
Allowance for loan losses: Ending balance: collectively evaluated for impairment	4,088	3,612		3,472		3,123				4,088	3,472	3,612	3,123	2,543
Loans receivables, Ending Balance	482,141	446,524		410,786		369,464				482,141	410,786	446,524	369,464	297,357
Loans receivables: Ending balance: individually evaluated for impairment	3,651	3,246		3,657		2,970				3,651	3,657	3,246	2,970	8,925
Loans Receivable: Ending balance: collectively evaluated for impairment	477,917	442,436		406,178		365,563				477,917	406,178	442,436	365,563	288,432
Commercial Portfolio [Member] | Commercial Real Estate [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivables, Ending Balance	573	842		951		931				573	951	842	931
Commercial Portfolio [Member] | Commercial Real Estate - Construction [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning Balance	101		120	119	153				33	144	153	153	33	9
Provisions	39			1						(4)	(33)	(9)	120	24
Allowance for Loan Losses, Ending Balance	140	144		120	119	153				140	120	144	153	33
Allowance for loan losses: Ending balance: individually evaluated for impairment	70	72								70		72
Allowance for loan losses: Ending balance: collectively evaluated for impairment	70	72		120		153				70	120	72	153	33
Loans receivables, Ending Balance	53,305	54,376		56,074		68,068				53,305	56,074	54,376	68,068	56,076
Loans receivables: Ending balance: individually evaluated for impairment	571	860								571		860
Loans Receivable: Ending balance: collectively evaluated for impairment	52,734	53,516		56,074		68,068				52,734	56,074	53,516	68,068	56,076
Finance Leases Portfolio [Member] | Lease Financing [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning Balance	1		1	1	1				2	1	1	1	2
Provisions													(1)	2
Allowance for Loan Losses, Ending Balance	1	1		1	1	1				1	1	1	1	2
Allowance for loan losses: Ending balance: collectively evaluated for impairment	1	1		1		1				1	1	1	1	2
Loans receivables, Ending Balance	307	425		565		727				307	565	425	727	1,121
Loans Receivable: Ending balance: collectively evaluated for impairment	307	425		565		727				307	565	425	727	1,121
Residential Portfolio [Member] | Residential Mortgage [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning Balance	532		521	516	534				450	541	534	534	450	581
Charge-offs										(18)		(4)	(35)	(133)
Recoveries	2			25						4	25	26	44	20
Provisions	5			(20)						12	(38)	(15)	75	(18)
Allowance for Loan Losses, Ending Balance	539	541		521	516	534				539	521	541	534	450
Allowance for loan losses: Ending balance: individually evaluated for impairment	66	68				23				66		68	23
Allowance for loan losses: Ending balance: collectively evaluated for impairment	473	473		521		511				473	521	473	511	450
Loans receivables, Ending Balance	102,637	99,457		103,822		100,665				102,637	103,822	99,457	100,665	66,442
Loans receivables: Ending balance: individually evaluated for impairment	968	916		824		1,361				968	824	916	1,361	1,146
Loans Receivable: Ending balance: collectively evaluated for impairment	101,345	98,152		102,628		98,904				101,345	102,628	98,152	98,904	65,296
Residential Portfolio [Member] | Residential Mortgage [Member] | Receivables Acquired with Deteriorated Credit Quality [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans receivables, Ending Balance	324	389		370		400				324	370	389	400
Consumer Portfolio [Member] | Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning Balance	3		9	9	12				35	3	12	12	35	72
Charge-offs	(10)			(7)						(16)	(10)	(42)	(14)	(33)
Recoveries	1			2						4	6	11	11	63
Provisions	10			5						13	1	22	(20)	(67)
Allowance for Loan Losses, Ending Balance	4	3		9	9	12				4	9	3	12	35
Allowance for loan losses: Ending balance: collectively evaluated for impairment	4	3		9		12				4	9	3	12	35
Loans receivables, Ending Balance	3,878	3,016		3,049		3,917				3,878	3,049	3,016	3,917	3,021
Loans Receivable: Ending balance: collectively evaluated for impairment	3,878	3,016		3,049		3,917				3,878	3,049	3,016	3,917	3,021
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan and lease losses, Beginning Balance	274		$ 323	287	206				$ 225	212	206	206	225	21
Provisions	(258)			36						(196)	117	6	(19)	204
Allowance for Loan Losses, Ending Balance	16	212		323	$ 287	206				16	323	212	206	225
Allowance for loan losses: Ending balance: collectively evaluated for impairment	$ 16	$ 212		$ 323		$ 206				$ 16	$ 323	$ 212	$ 206	$ 225

Loans and Allowance for Loan 78

Loans and Allowance for Loan and Lease Losses (Troubled Debt Restructurings) (Detail)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017USD ($)Loans	Jun. 30, 2016Loans	Jun. 30, 2017USD ($)Loans	Jun. 30, 2016Loans	Dec. 31, 2016USD ($)LoansContract	Dec. 31, 2015USD ($)
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts | Loans	0	0	0	0	0
Financing Receivable, Modifications, Pre-Modification Recorded Investment			$ 4,216,000		$ 5,368,000	$ 4,407,000
Financing Receivable, Modifications, Post-Modification Recorded Investment			4,746,000		4,823,000	3,879,000
Financing Receivable, Modifications, Recorded Investment	$ 3,030,000		3,030,000		$ 3,515,000	2,805,000
Entity Loan Modification Program [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts | Contract					3
Financing Receivable, Modifications, Pre-Modification Recorded Investment					$ 1,002,000
Financing Receivable, Modifications, Post-Modification Recorded Investment					982,000
Financing Receivable, Modifications, Recorded Investment					982,000
Commercial Portfolio [Member] | Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment					40,000	40,000
Financing Receivable, Modifications, Post-Modification Recorded Investment					35,000	35,000
Financing Receivable, Modifications, Recorded Investment					5,000	15,000
Commercial Portfolio [Member] | Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment			3,457,000		4,569,000	3,634,000
Financing Receivable, Modifications, Post-Modification Recorded Investment			4,003,000		4,031,000	3,117,000
Financing Receivable, Modifications, Recorded Investment	2,407,000		2,407,000		$ 2,871,000	2,235,000
Commercial Portfolio [Member] | Commercial Real Estate [Member] | Entity Loan Modification Program [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts | Contract					2
Financing Receivable, Modifications, Pre-Modification Recorded Investment					$ 934,000
Financing Receivable, Modifications, Post-Modification Recorded Investment					914,000
Financing Receivable, Modifications, Recorded Investment					914,000
Residential Portfolio [Member] | Residential Mortgage [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment			759,000		759,000	733,000
Financing Receivable, Modifications, Post-Modification Recorded Investment			743,000		757,000	727,000
Financing Receivable, Modifications, Recorded Investment	$ 623,000		$ 623,000		$ 639,000	$ 555,000
Residential Portfolio [Member] | Residential Mortgage [Member] | Entity Loan Modification Program [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Number of Contracts | Contract					1
Financing Receivable, Modifications, Pre-Modification Recorded Investment					$ 68,000
Financing Receivable, Modifications, Post-Modification Recorded Investment					68,000
Financing Receivable, Modifications, Recorded Investment					$ 68,000

Loans and Allowance for Loan 79

Loans and Allowance for Loan and Lease Losses (Schedule of Accretion of Purchased Impaired Loan) (Detail) - USD ($) $ in Thousands		3 Months Ended	6 Months Ended	12 Months Ended
		Jun. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Accretable yield, beginning balance		$ 80	$ 67	$ 178
Accretable yield amortized to interest income		(12)	(22)	(141)
Reclassification from nonaccretable difference	[1]		23	30
Accretable yield, ending balance		$ 68	$ 68	$ 67
[1]	Reclassification from non-accretable difference represents an increase to the estimated cash flows to be collected on the underlying portfolio.

Bank Premises and Equipment (Pr

Bank Premises and Equipment (Premises and Equipment) (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Total cost		$ 21,537	$ 23,667
Less accumulated depreciation		(10,463)	(9,674)
Net book value of bank premises and equipment	$ 11,190	11,074	13,993
Assets held for sale		1,894
Total bank premises and equipment		12,968	13,993
Land [Member]
Property, Plant and Equipment [Line Items]
Total cost		2,315	2,906
Buildings [Member]
Property, Plant and Equipment [Line Items]
Total cost		9,517	10,789
Furniture, Fixtures, and Equipment [Member]
Property, Plant and Equipment [Line Items]
Total cost		8,184	8,742
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Total cost		1,432	1,212
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Total cost		$ 89	$ 18

Bank Premises and Equipment (Na

Bank Premises and Equipment (Narrative) (Detail)	Jan. 20, 2017USD ($)Property	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Dec. 31, 2016USD ($)Lease	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Property, Plant and Equipment [Line Items]
Depreciation		$ 715,000	$ 820,000	$ 1,658,000	$ 1,485,000	$ 1,235,000
Asset held for sale, description				As of December 31, 2016, assets held-for-sale consisted of three full service retail banking properties. These properties were transferred from land and buildings to assets held for sale due to Mid Penn’s intent to sell them during January 2017
Number of properties sale | Property	3
Proceeds from sale of three properties	$ 2,240,000	2,201,000
Gain from sale of three properties	$ 346,000	$ (26,000)		$ (142,000)		(18,000)
2,017				1,121,000
2,018				1,115,000
2,019				1,116,000
2,020				793,000
2,021				582,000
thereafter				$ 5,666,000
Lease expiration date				Dec. 31, 2035
Sublease to Unrelated Party [Member]
Property, Plant and Equipment [Line Items]
Number of operating lease with related parties | Lease				2
Lease expiration date				Mar. 31, 2021
Operating Leases Related Party [Member]
Property, Plant and Equipment [Line Items]
Number of operating lease with related parties | Lease				4
Operating leases, rent expense, net				$ 348,000	$ 279,000	$ 54,000
2,017				346,000
2,018				302,000
2,019				304,000
2,020				305,000
2,021				213,000
thereafter				$ 2,118,000
Second Sublease Agreement [Member] | Sublease to Unrelated Party [Member]
Property, Plant and Equipment [Line Items]
Sale and lease back of properties, description	Two of the properties are being leased back by Mid Penn for a period of at least 15 years, and the respective gains on the sales of those properties will be recognized over the life of the leases.
Lease agreement start date				Jul. 1, 2016
First Sublease Agreement [Member] | Sublease to Unrelated Party [Member]
Property, Plant and Equipment [Line Items]
Lease agreement start date				Apr. 1, 2016
Minimum [Member]
Property, Plant and Equipment [Line Items]
Length Of Lease	15 years
Other Expense [Member]
Property, Plant and Equipment [Line Items]
Asset held for sale, impairment charge on one of the properties				$ 142,000

Bank Premises and Equipment (Fu

Bank Premises and Equipment (Future Minimum Rental Payments) (Detail) $ in Thousands	Dec. 31, 2016USD ($)
Property, Plant and Equipment [Abstract]
2017 Lease obligation	$ 1,121
2018 Lease obligation	1,115
2019 Lease obligation	1,116
2020 Lease obligation	793
2021 Lease obligation	582
Lease obligation thereafter	5,666
Lease obligation	10,393
2017 Sublease rental income	74
2018 Sublease rental income	79
2019 Sublease rental income	81
2020 Sublease rental income	81
2021 Sublease rental income	20
Sublease rental income	335
2017 Net rental expense	1,047
2018 Net rental expense	1,036
2019 Net rental expense	1,035
2020 Net rental expense	712
2021 Net rental expense	562
2021 Net rental thereafter	5,666
Net rental expense	$ 10,058

Bank Premises and Equipment (83

Bank Premises and Equipment (Future Minimum Rental Payments) (Parenthetical) (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Abstract]
Rent expense in connection with leases	$ 716,000	$ 627,000	$ 151,000

Deposits (Narrative) (Detail)

Deposits (Narrative) (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jun. 30, 2017
Time Deposits	$ 182,595,000	$ 160,849,000		$ 204,235,000
Interest Expense, Time Deposits	2,156,000	1,920,000	$ 1,971,000
Brokered Deposits	13,567,000	11,168,000
Related Party Deposit Liabilities	19,279,000	17,163,000
Demand Deposit [Member]
Demand deposit overdrafts reclassified as loans	$ 285,000	$ 567,000

Deposits (Time Deposits By Matu

Deposits (Time Deposits By Maturity Date) (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Time Deposits, Total	$ 204,235	$ 182,595	$ 160,849
Time Deposits Less Than $250,000 [Member]
Maturing in 2017		64,993
Maturing in 2018		35,238
Maturing in 2019		20,094
Maturing in 2020		20,997
Maturing in 2021		13,953
Maturing thereafter		738
Time Deposits, Total		156,013
Time Deposits $250,000 or More [Member]
Maturing in 2017		16,760
Maturing in 2018		5,360
Maturing in 2019		3,209
Maturing in 2020		950
Maturing in 2021		303
Maturing thereafter		0
Time Deposits, Total		$ 26,582

Short-term Borrowings (Narrativ

Short-term Borrowings (Narrative) (Detail) - USD ($)	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Short-term Debt [Line Items]
Short term borrowings	$ 21,468,000		$ 31,596,000
Current borrowing available		$ 404,204,000
Federal Funds Purchased [Member]
Short-term Debt [Line Items]
Short term borrowings		0	$ 31,596,000
Short-term debt, weighted average interest rate			0.40%
Correspondent Banks [Member]
Short-term Debt [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity		$ 15,000,000

Long-term Debt (Narrative) (Det

Long-term Debt (Narrative) (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Maturities of Long-term Debt [Abstract]
Long-term debt outstanding	$ 13,467	$ 13,581	$ 40,305
Long-Term Debt, Aggregate Principal Amounts Due, 2017		1,229
Long-Term Debt, Aggregate Principal Amounts Due, 2018		223
Long-Term Debt, Aggregate Principal Amounts Due, 2019		10,235
Long-Term Debt, Aggregate Principal Amounts Due, 2020		246
Long-Term Debt, Aggregate Principal Amounts Due, 2021		258
Long-Term Debt, Aggregate Principal Amounts Due, Thereafter		$ 1,390

Long-term Debt (Long-term Debt

Long-term Debt (Long-term Debt Outstanding by Maturity Date) (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Long-term debt outstanding	$ 13,467	$ 13,581	$ 40,305
Maturing in 2016 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding			$ 26,521
Maturing in 2016 [Member] | Minimum [Member]
Debt Instrument [Line Items]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate		0.54%	0.54%
Maturing in 2016 [Member] | Maximum [Member]
Debt Instrument [Line Items]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate		1.08%	1.08%
Maturing in 2017 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding		$ 1,016	$ 1,016
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate		3.03%	3.03%
Maturing In 2019 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding		$ 10,000	$ 10,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate		1.87%	1.87%
Maturing in 2026 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding		$ 2,504	$ 2,703
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate		4.80%	4.80%
Maturing in 2027 [Member]
Debt Instrument [Line Items]
Long-term debt outstanding		$ 61	$ 65
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate		6.71%	6.71%

Subordinated Debt (Narrative) (

Subordinated Debt (Narrative) (Detail) - USD ($)	Dec. 09, 2015	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Subordinated debt issuance				$ 7,500,000
Notes Due 2025 [Member] | Subordinated Debt [Member]
Subordinated debt issuance	$ 7,500,000
Debt instrument, interest rate, effective percentage	5.15%
Debt Instrument, Description of Variable Rate Basis		Notes bear interest at a rate of 5.15% per year for the first five years and then float at the Wall Street Journal's Prime Rate plus 0.50%, provided that the interest rate applicable to the outstanding principal balance will at no time be less than 4.0%.	Notes bear interest at a rate of 5.15% per year for the first five years and then float at the Wall Street Journal’s Prime Rate plus 0.50%, provided that the interest rate applicable to the outstanding principal balance will at no times be less than 4.0%.
Debt Instrument, Payment Terms		Interest will be payable quarterly in arrears on January 1, April 1, July 1 and October 1 of each year, beginning on January 1, 2016.	Interest will be payable quarterly in arrears on January 1, April 1, July 1 and October 1 of each year, and began on January 1, 2016.
Debt instrument, maturity date		Dec. 9, 2025	Dec. 9, 2025
Debt Instrument, Redemption, Description		The Notes will mature on December 9, 2025 and are redeemable in whole or in part, without premium or penalty, at any time on or after December 9, 2020, and prior to December 9, 2025. Additionally, Mid Penn may redeem the Notes in whole at any time, or in part from time to time, upon at least 30 days’ notice if: (i) a change or prospective change in law occurs that could prevent Mid Penn from deducting interest payable on the Notes for U.S. federal income tax purposes; (ii) an event occurs that precludes the Notes from being recognized as Tier 2 capital for regulatory capital purposes; or (iii) Mid Penn becomes required to register as an investment company under the Investment Company Act of 1940, as amended, in each case at 100% of the principal amount of the subordinated notes, plus accrued and unpaid interest thereon to but excluding the date of redemption.	The Notes will mature on December 9, 2025 and are redeemable in whole or in part, without premium or penalty, at any time on or after December 9, 2020, and prior to December 9, 2025. Additionally, Mid Penn may redeem the Notes in whole at any time, or in part from time to time, upon at least 30 days’ notice if: (i) a change or prospective change in law occurs that could prevent Mid Penn from deducting interest payable on the Notes for U.S. federal income tax purposes; (ii) an event occurs that precludes the Notes from being recognized as Tier 2 capital for regulatory capital purposes; or (iii) Mid Penn becomes required to register as an investment company under the Investment Company Act of 1940, as amended, in each case at 100% of the principal amount of the subordinated notes, plus accrued and unpaid interest thereon to but excluding the date of redemption.
Notes payable to related parties			$ 1,930,000
Unamortized debt issuance cost		$ 81,000	$ 86,000
Notes Due 2025 [Member] | Subordinated Debt [Member] | WSJ Prime Rate [Member]
Debt instrument, interest rate, effective percentage	4.00%
Debt Instrument, Basis Spread on Variable Rate	0.50%

Fair Value Measurement (Assets

Fair Value Measurement (Assets Measured at Fair Value on Recurring Basis) (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	$ 111,353	$ 133,625	$ 135,721
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	1,143	2,920	3,101
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	110,210	130,705	132,620
U.S. Treasury and U.S. government agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	41,771	47,012	26,990
U.S. Treasury and U.S. government agencies [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities		1,864	1,861
U.S. Treasury and U.S. government agencies [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	41,771	45,148	25,129
Mortgage-backed U.S. Government Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	28,239	25,619	38,804
Mortgage-backed U.S. Government Agencies [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	28,239	25,619	38,804
State and political subdivision obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	39,095	58,838	66,617
State and political subdivision obligations [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	39,095	58,838	66,617
Corporate debt securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	1,105	1,100	2,070
Corporate debt securities [Member] | Scenario, Previously Reported [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities		1,000
Corporate debt securities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	1,105	1,100	2,070
Corporate debt securities [Member] | Level 2 [Member] | Scenario, Previously Reported [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities		1,000
Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	1,143	1,056	1,240
Equity Securities [Member] | Scenario, Previously Reported [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities		1,156
Equity Securities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	$ 1,143	1,056	$ 1,240
Equity Securities [Member] | Level 1 [Member] | Scenario, Previously Reported [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities		1,056
Equity Securities [Member] | Level 2 [Member] | Scenario, Previously Reported [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities		$ 100

Fair Value Measurement (Fair Va

Fair Value Measurement (Fair Value Measurements, Nonrecurring) (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Impaired Loan [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	$ 2,061	$ 2,404	$ 2,088
Impaired Loan [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	2,061	2,404	2,088
Foreclosed Assets Held for Sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring		135	453
Foreclosed Assets Held for Sale [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring		135	453
Mortgage Servicing Rights [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	135	144	174
Mortgage Servicing Rights [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	$ 135	$ 144	$ 174

Fair Value Measurement (Fair 92

Fair Value Measurement (Fair Value Inputs, Assets, Quantitative Information) (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Impaired Loan [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	$ 2,061	$ 2,404	$ 2,088
Fair Value Measurements, Valuation Techniques	Appraisal of collateral	Appraisal of collateral	Appraisal of collateral
Fair Value Disclosure, Unobservable Input Range	Appraisal adjustments	Appraisal adjustments	Appraisal adjustments
Impaired Loan [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	$ 2,061	$ 2,404	$ 2,088
Foreclosed Assets Held for Sale [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring		$ 135	$ 453
Fair Value Measurements, Valuation Techniques	Appraisal of collateral	Appraisal of collateral	Appraisal of collateral
Fair Value Disclosure, Unobservable Input Range	Appraisal adjustments	Appraisal adjustments	Appraisal adjustments
Foreclosed Assets Held for Sale [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring		$ 135	$ 453
Mortgage Servicing Rights [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	$ 135	$ 144	$ 174
Fair Value Measurements, Valuation Techniques	Multiple of annual service fee	Multiple of annual service fee	Multiple of annua service fee
Fair Value Disclosure, Unobservable Input Range	Estimated prepayment speed	Estimated prepayment speed based on rate and term	Estimated prepayment speed based on rate and term
Mortgage Servicing Rights [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure, Nonrecurring	$ 135	$ 144	$ 174
Minimum [Member] | Appraisal of Collateral [Member] | Impaired Loan [Member] | Unobservable Input - Appraisal Adjustments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	26.00%	11.00%	11.00%
Minimum [Member] | Appraisal of Collateral [Member] | Foreclosed Assets Held for Sale [Member] | Unobservable Input - Appraisal Adjustments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	0.00%	26.00%	17.00%
Minimum [Member] | Multiple of Annual Service [Member] | Mortgage Servicing Rights [Member] | Unobservable Input Estimated Prepayment Speed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Prepayment Rate	210.00%	210.00%	210.00%
Maximum [Member] | Appraisal of Collateral [Member] | Impaired Loan [Member] | Unobservable Input - Appraisal Adjustments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	43.00%	70.00%	60.00%
Maximum [Member] | Appraisal of Collateral [Member] | Foreclosed Assets Held for Sale [Member] | Unobservable Input - Appraisal Adjustments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	0.00%	31.00%	27.00%
Maximum [Member] | Multiple of Annual Service [Member] | Mortgage Servicing Rights [Member] | Unobservable Input Estimated Prepayment Speed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Prepayment Rate	400.00%	400.00%	400.00%
Weighted Average [Member] | Appraisal of Collateral [Member] | Impaired Loan [Member] | Unobservable Input - Appraisal Adjustments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	35.00%	30.00%	30.00%
Weighted Average [Member] | Appraisal of Collateral [Member] | Foreclosed Assets Held for Sale [Member] | Unobservable Input - Appraisal Adjustments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Discount Rate	0.00%	27.00%	26.00%
Weighted Average [Member] | Multiple of Annual Service [Member] | Mortgage Servicing Rights [Member] | Unobservable Input Estimated Prepayment Speed [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Prepayment Rate	365.00%	365.00%	360.00%

Fair Value Measurement (Fair 93

Fair Value Measurement (Fair Value, by Balance Sheet Grouping) (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available for sale investment securities	$ 111,353	$ 133,625	$ 135,721
Held-to-maturity investment securities	71,199	0
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	29,179	45,973	13,284
Interest-bearing time balances with other financial institutions			4,317
Available for sale investment securities	111,353	133,625	135,721
Held-to-maturity investment securities	71,096
Loans held for sale	2,369	1,959
Net loans and leases	854,594	806,741	730,345
Restricted investment in bank stocks	3,985	2,443	4,266
Accrued interest receivable	3,991	3,928	3,813
Mortgage servicing rights	135	144	174
Deposits	987,468	935,373	777,043
Short-term borrowings	21,468		31,596
Long-term debt	13,467	13,581	40,305
Subordinated debt	7,419	7,414	7,500
Accrued interest payable	788	515	390
Commitments to extend credit	0	0
Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents	29,179	45,973	13,284
Interest-bearing time balances with other financial institutions			4,317
Available for sale investment securities	111,353	133,625	135,721
Held-to-maturity investment securities	71,199
Loans held for sale	2,369	1,959
Net loans and leases	874,192	824,293	738,773
Restricted investment in bank stocks	3,985	2,443	4,266
Accrued interest receivable	3,991	3,928	3,813
Mortgage servicing rights	135	144	174
Deposits	988,200	935,075	777,320
Short-term borrowings	21,468		31,596
Long-term debt	12,149	13,614	39,626
Subordinated debt	7,420	7,534	7,500
Accrued interest payable	788	515	$ 390
Commitments to extend credit	$ 0	$ 0

Fair Value Measurements (Schedu

Fair Value Measurements (Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis) (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity investment securities	$ 71,199	$ 0
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity investment securities	71,199
Deposits	988,200	935,075	$ 777,320
Short-term borrowings	21,468
Long-term debt	12,149	13,614	39,626
Subordinated debt	7,420	7,534
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net loans and leases	874,192	824,293	738,773
Carrying Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity investment securities	71,096
Net loans and leases	854,594	806,741	730,345
Deposits	987,468	935,373	777,043
Short-term borrowings	21,468		31,596
Long-term debt	13,467	13,581	40,305
Subordinated debt	7,419	7,414	7,500
Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity investment securities	71,199
Net loans and leases	874,192	824,293	738,773
Deposits	988,200	935,075	777,320
Short-term borrowings	21,468		31,596
Long-term debt	12,149	13,614	39,626
Subordinated debt	$ 7,420	$ 7,534	$ 7,500

Postretirement Benefit Plans (N

Postretirement Benefit Plans (Narrative) (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Postretirement benefit health insurance reimbursable premium, maximum	$ 5,000
Defined Benefit Postretirement Health Insurance [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, minimum retirement age	55 years
Defined Benefit Plan, Minimum Service Period Requirement	20 years
Defined benefit plan, maximum coverage period	5 years
Defined Benefit Postretirement Life Insurance [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, minimum retirement age	55 years
Defined Benefit Plan, Minimum Service Period Requirement	20 years
Defined Benefit Plan, Benefit Description, Prior To Age 65	be three times the participant's annual salary at retirement or $50,000, whichever is less
Prior to age 65, life insurance maximum, coverage amount	$ 50,000
Defined Benefit Plan, Benefit Description, After Age 65	life insurance coverage amount will decrease by 10% per year, subject to a minimum amount of $5,000
Life insurance minimum amount coverage	$ 5,000
Director's Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Unrecognized Prior Service Cost Generated By Adoption of the Plan	274,000
Defined Benefit Plan, Amounts Recognized in Other Comprehensive Income (Loss), Net Prior Service Cost, before Tax	43,000
Defined Benefit Plan, Accumulated Benefit Obligation	1,122,000	$ 1,150,000
Defined Benefit Plan, Amount to be Amortized from Accumulated Other Comprehensive Income (Loss) Next Fiscal Year	21,525
Cash surrender value of bank owned life insurance	3,834,000	3,764,000
Defined Benefit Postretirement Health And Life Coverage [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Benefit Obligation	540,000	$ 572,000
Defined Benefit Plan, Amount to be Amortized from Accumulated Other Comprehensive Income (Loss) Next Fiscal Year	$ 34,898

Postretirement Benefit Plans 96

Postretirement Benefit Plans (Net Funded Status) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Postretirement Health And Life Coverage [Member]
Change in benefit obligations:
Benefit obligations	$ 572	$ 861
Change in benefit obligations: Service cost	4	13	$ 13
Change in benefit obligations: Interest cost	23	32	38
Change in benefit obligations: Change in experience	2	(24)
Change in benefit obligations: Change in assumptions	13	(4)
Change in benefit obligations: Change due to plan amendment		(244)
Change in benefit obligations/fair value of plan assets: Benefit payments	(74)	(62)
Benefit obligations	540	572	861
Change in fair value of plan assets:
Fair value of plan assets	0	0
Change in fair value of plan assets: Employer contributions	74	62
Change in benefit obligations/fair value of plan assets: Benefit payments	(74)	(62)
Fair value of plan assets	0	0	0
Funded status at year end	(540)	(572)
Director's Retirement Plan [Member]
Change in benefit obligations:
Benefit obligations	1,150	1,186
Change in benefit obligations: Service cost	34	33	33
Change in benefit obligations: Interest cost	46	45	51
Change in benefit obligations: Actuarial gain	(13)	(8)
Change in benefit obligations: Change in assumptions	(4)	(16)
Change in benefit obligations/fair value of plan assets: Benefit payments	(91)	(90)
Benefit obligations	1,122	1,150	1,186
Change in fair value of plan assets:
Fair value of plan assets	0	0
Change in fair value of plan assets: Employer contributions	91	90
Change in benefit obligations/fair value of plan assets: Benefit payments	(91)	(90)
Fair value of plan assets	0	0	$ 0
Funded status at year end	$ (1,122)	$ (1,150)

Postretirement Benefit Plans (A

Postretirement Benefit Plans (Amounts Recognized in Balance Sheet) (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Postretirement Health And Life Coverage [Member]
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	$ 540	$ 572
Director's Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Accrued benefit liability	$ 1,122	$ 1,150

Postretirement Benefit Plans 98

Postretirement Benefit Plans (Amounts Recognized in Other Comprehensive (Loss) Income) (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Postretirement Health And Life Coverage [Member]
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain), pretax	$ (31)	$ (47)
Net prior service cost, pretax	(209)	(244)
Director's Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain), pretax	60	77
Net prior service cost, pretax	$ 43	$ 64

Postretirement Benefit Plans 99

Postretirement Benefit Plans (Net Periodic (Income) Benefit Costs) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Postretirement Health And Life Coverage [Member]
Defined Benefit Plan Disclosure [Line Items]
Service Cost	$ 4	$ 13	$ 13
Interest Cost	23	32	38
Amortization of prior service cost	(35)		(1)
Net periodic benefit cost	(8)	45	50
Director's Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service Cost	34	33	33
Interest Cost	46	45	51
Amortization of prior service cost	22	22	22
Net periodic benefit cost	$ 102	$ 100	$ 106

Postretirement Benefit Plans100

Postretirement Benefit Plans (Assumptions Used) (Detail)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Postretirement Health And Life Coverage [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	4.00%	4.25%
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Rate of Compensation Increase	3.00%	3.25%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	4.25%	4.00%	4.75%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Rate of Compensation Increase	3.25%	3.00%	3.75%
Director's Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	4.00%	4.25%
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Change In Consumer Price Index	2.00%	2.25%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate	4.25%	4.00%	4.75%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Changes In Consumer Price Index	2.25%	2.25%	2.75%

Postretirement Benefit Plans (H

Postretirement Benefit Plans (Health Care Cost Trend Rates) (Detail) - Defined Benefit Postretirement Health And Life Coverage [Member]	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Health care cost trend rate assumed for next year	6.00%	5.50%	6.50%
Rate to which the cost trend rate is assumed to decline (the ultimate trend rate)	5.50%	5.50%	5.50%
Year that the rate reaches the ultimate trend rate	2,018	2,016	2,016

Postretirement Benefit Plans (E

Postretirement Benefit Plans (Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates) (Detail) - Defined Benefit Postretirement Health And Life Coverage [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Effect of One Percentage Point Increase on Service and Interest Cost Components	$ 0
Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation	3
Defined Benefit Plan, Effect of One Percentage Point Decrease on Service and Interest Cost Components	0
Defined Benefit Plan, Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation	$ 3

Postretirement Benefit Plans103

Postretirement Benefit Plans (Expected Benefit Payments) (Detail)	12 Months Ended
	Dec. 31, 2016USD ($)
Defined Benefit Postretirement Health And Life Coverage [Member]
Defined Benefit Plan Disclosure [Line Items]
1/1/2017 to 12/31/2017	$ 73,000
1/1/2018 to 12/31/2018	64,000
1/1/2019 to 12/31/2019	61,000
1/1/2020 to 12/31/2020	56,000
1/1/2021 to 12/31/2021	30,000
1/1/2022 to 12/31/2026	156,000
Defined contribution plan, employer discretionary contribution amount	73,000
Director's Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
1/1/2017 to 12/31/2017	94,000
1/1/2018 to 12/31/2018	96,000
1/1/2019 to 12/31/2019	96,000
1/1/2020 to 12/31/2020	98,000
1/1/2021 to 12/31/2021	108,000
1/1/2022 to 12/31/2026	464,000
Defined contribution plan, employer discretionary contribution amount	$ 94,000

Other Benefit Plans (Narrative)

Other Benefit Plans (Narrative) (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Deferred Compensation Arrangement with Individual, by Type of Compensation, Pension and Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Deferred Compensation Arrangement with Individual, Recorded Liability	$ 143,000	$ 160,000
Deferred compensation arrangement with individual, compensation expense	6,000	9,000	$ 6,000
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, associated expense	0	0	0
Director's Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Deferred Compensation Arrangement with Individual, Recorded Liability	606,000	523,000
Deferred compensation arrangement with individual, compensation expense	21,000	17,000	16,000
Cash surrender value of bank owned life insurance	3,834,000	3,764,000
Salary Continuation Agreement [Member]
Defined Benefit Plan Disclosure [Line Items]
Deferred Compensation Arrangement with Individual, Recorded Liability	254,000	237,000
Deferred compensation arrangement with individual, compensation expense	$ 17,000	16,000	15,000
Defined benefit plan, maximum coverage period	15 years
Cash surrender value of bank owned life insurance	$ 1,284,000	1,253,000
Split Dollar Life Insurance Arrangements [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash surrender value of bank owned life insurance	1,801,000	1,806,000
Split Dollar Life Insurance Arrangements [Member] | Phoenix Bancorp Inc. [Member]
Defined Benefit Plan Disclosure [Line Items]
Cash surrender value of bank owned life insurance	3,838,000	3,749,000
401(k) Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, associated expense	$ 362,000	$ 321,000	$ 216,000

Other Benefit Plans (Schedule o

Other Benefit Plans (Schedule of Employees Eligible to Participate in Employee Stock Purchase Plan) (Detail) - $ / shares	6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Pension Plans And Defined Benefit Postretirement Plans Disclosure [Abstract]
ESPP shares purchased	1,940	2,289	4,465	4,162	3,432
Average purchase price per share			$ 18.520	$ 15.865	$ 15.318

Federal Income Taxes (Net Defer

Federal Income Taxes (Net Deferred Tax Asset) (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Deferred Tax Assets, Allowance for loan and lease losses	$ 2,442	$ 2,097
Deferred Tax Assets, Loan Fees	82	79
Deferred Tax Assets, Deferred Compensation	906	313
Deferred Tax Assets, Benefit plans	955	586
Deferred Tax Assets, Unrealized loss on securities	1,504
Deferred Tax Assets, Nonaccrual interest		554
Deferred Tax Assets, Business combination adjustments	720	1,166
Deferred Tax Assets, Other	177	170
Deferred Tax Assets, Gross, Total	6,786	4,965
Deferred Tax Liabilities, Depreciation	(1,175)	(1,074)
Deferred Tax Liabilities, Bond accretion	(117)	(111)
Deferred Tax Liabilities, Goodwill and intangibles	(500)	(472)
Deferred Tax Liabilities, Unrealized gain on securities		(806)
Deferred Tax Liabilities, Prepaid expenses	(312)	(240)
Deferred Tax Liabilities, Business combination adjustments	(367)	(428)
Deferred Tax Liabilities, Other	(29)	(13)
Deferred Tax Liabilities, Gross, Total	(2,500)	(3,144)
Deferred tax asset, net	$ 4,286	$ 1,821

Federal Income Taxes (Provision

Federal Income Taxes (Provision for Income Taxes) (Detail) - USD ($) $ in Thousands	3 Months Ended									6 Months Ended		12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Current expense												$ 2,613	$ 647	$ 1,574
Deferred (benefit) expense										$ (65)	$ 16	(336)	997	(112)
Provision for income taxes	$ 769	$ 638	$ 526	$ 593	$ 520	$ 421	$ 546	$ 593	$ 84	$ 1,459	$ 1,113	$ 2,277	$ 1,644	$ 1,462

Federal Income Taxes (Narrative

Federal Income Taxes (Narrative) (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Federal tax rate	34.00%	34.00%	34.00%
Unrecognized tax benefits that would affect the effective income tax rate if recognized	$ 0
Income Tax Examination, Penalties and Interest Expense	0	$ 0	$ 0
Income Tax Examination, Penalties and Interest Accrued	$ 0	$ 0

Federal Income Taxes (Schedule

Federal Income Taxes (Schedule of Effective Income Tax Rate Reconciliation) (Detail) - USD ($) $ in Thousands	3 Months Ended									6 Months Ended		12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Provision at the expected statutory rate												$ 3,428	$ 2,779	$ 2,435
Effect of tax-exempt income												(1,089)	(1,105)	(1,086)
Effect of investment in life insurance												(90)	(91)	(68)
Nondeductible interest												41	37	42
Nondeductible merger and acquisition expense													34	163
Other items												(13)	(10)	(24)
Provision for income taxes	$ 769	$ 638	$ 526	$ 593	$ 520	$ 421	$ 546	$ 593	$ 84	$ 1,459	$ 1,113	$ 2,277	$ 1,644	$ 1,462

Regulatory Matters (Detail)

Regulatory Matters (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital for Capital Adequacy (To Average Assets), Ratio	4.00%
Common Equity Tier 1 Capital for Capital Adequacy (to Risk Weighted Assets), ratio	4.50%
Tier 1 Capital for Capital Adequacy (To Risk Weighted Assets), Ratio	6.00%	4.00%
Total Capital for Capital Adequacy (To Risk Weighted Assets), Ratio	8.00%
Capital Conservation Buffer Percentage	2.50%
Common Equity Tier 1 Capital Ratio with Capital Conservation Buffer	7.00%
Tier 1 Capital Ratio with Capital Conservation Buffer	8.50%
Total Capital Ratio with Capital Conservation Buffer	10.50%
Annual Phase in Percentage of Capital Conservation Buffer	0.625%
Capital Conservation Buffer Phase in Beginning Year Month	2016-01
Capital Conservation Buffer Phase in End Year Month	2019-01
Statutory Accounting Practices, Statutory Amount Available for Dividend Payments without Regulatory Approval	$ 5,311
Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital (To Average Assets)	77,026	$ 70,351
Common Equity Tier 1 Capital (to Risk Weighted Assets)	77,026	70,351
Tier 1 Capital (To Risk Weighted Assets)	77,026	70,351
Total Capital (To Risk Weighted Assets)	$ 84,329	$ 76,614
Tier 1 Capital (to Average Assets), Ratio	7.40%	7.80%
Common Equity Tier 1 Capital (to Risk Weighted Assets), ratio	10.00%	10.00%
Tier 1 Capital (To Risk Weighted Assets), Ratio	10.00%	10.00%
Total Capital (To Risk Weighted Assets), Ratio	10.90%	10.90%
Tier 1 Capital for Capital Adequacy (To Average Assets)	$ 41,568	$ 36,245
Common Equity Tier 1 Capital for Capital Adequacy (to Risk Weighted Assets)	34,781	31,698
Tier 1 Capital for Capital Adequacy (To Risk Weighted Assets)	46,374	42,264
Total Capital for Capital Adequacy (To Risk Weighted Assets)	$ 61,832	$ 56,352
Tier 1 Capital for Capital Adequacy (To Average Assets), Ratio	4.00%	4.00%
Common Equity Tier 1 Capital for Capital Adequacy (to Risk Weighted Assets), ratio	4.50%	4.50%
Tier 1 Capital for Capital Adequacy (To Risk Weighted Assets), Ratio	6.00%	6.00%
Total Capital for Capital Adequacy (To Risk Weighted Assets), Ratio	8.00%	8.00%
Tier 1 Capital to be Well-Capitalized Under Prompt Corrective Action Provision (To Average Assets)	$ 51,960	$ 45,306
Common Equity Tier 1 Capital to be Well-Capitalized Under Prompt Corrective Action Provision (To Risk Weighted Assets)	50,239	45,786
Tier 1 Capital to be Well-Capitalized Under Prompt Corrective Action Provision (To Risk Weighted Assets)	61,832	56,352
Total Capital to be Well-Capitalized Under Prompt Corrective Action Provision (To Risk Weighted Assets)	$ 77,291	$ 70,440
Tier 1 Capital to be Well-Capitalized Under Prompt Corrective Action Provision (To Average Assets), Ratio	5.00%	5.00%
Common Equity Tier 1 Capital to be Well-Capitalized Under Prompt Corrective Action Provision (To Risk Weighted Assets), ratio	6.50%	6.50%
Tier 1 Capital to be Well-Capitalized Under Prompt Corrective Action Provision (To Risk Weighted Assets), Ratio	8.00%	8.00%
Total Capital to be Well-Capitalized Under Prompt Corrective Action Provision (To Risk Weighted Assets), Ratio	10.00%	10.00%
Parent Company [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital (To Average Assets)	$ 70,431	$ 64,089
Common Equity Tier 1 Capital (to Risk Weighted Assets)	70,431	64,089
Tier 1 Capital (To Risk Weighted Assets)	70,431	64,089
Total Capital (To Risk Weighted Assets)	$ 85,148	$ 77,852
Tier 1 Capital (to Average Assets), Ratio	6.80%	7.30%
Common Equity Tier 1 Capital (to Risk Weighted Assets), ratio	9.10%	9.10%
Tier 1 Capital (To Risk Weighted Assets), Ratio	9.10%	9.10%
Total Capital (To Risk Weighted Assets), Ratio	11.00%	11.00%
Tier 1 Capital for Capital Adequacy (To Average Assets)	$ 41,595	$ 35,098
Common Equity Tier 1 Capital for Capital Adequacy (to Risk Weighted Assets)	34,807	31,731
Tier 1 Capital for Capital Adequacy (To Risk Weighted Assets)	46,409	42,308
Total Capital for Capital Adequacy (To Risk Weighted Assets)	$ 61,879	$ 56,410
Tier 1 Capital for Capital Adequacy (To Average Assets), Ratio	4.00%	4.00%
Common Equity Tier 1 Capital for Capital Adequacy (to Risk Weighted Assets), ratio	4.50%	4.50%
Tier 1 Capital for Capital Adequacy (To Risk Weighted Assets), Ratio	6.00%	6.00%
Total Capital for Capital Adequacy (To Risk Weighted Assets), Ratio	8.00%	8.00%

Concentration of Risk and Off-B

Concentration of Risk and Off-Balance Sheet Risk (Narrative) (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Concentration Risk [Line Items]
Commitments to extend credit	$ 201,749,000	$ 157,338,000
Balance of loans sold under the program	$ 9,206,000	5,958,000
Concentration risk, benchmark description	10% or more of the Bank's total net loans outstanding
Benchmark - Loans Receivable, Net [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	48.80%
Financial Standby Letters of Credit [Member]
Concentration Risk [Line Items]
Commitments to extend credit	$ 14,000,000	$ 15,805,000

Common Stock (Detail)

Common Stock (Detail) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jun. 25, 2014
2014 Restricted Stock Plan [Member]
Class of Stock [Line Items]
Shares authorized per plan								100,000
Shares granted, net					16,045
Shares granted			16,045		7,540	5,475	3,500
Shares cancelled					470
Unrecognized compensation cost related to all non-vested share-based compensation awards					$ 215,000
Granted shares unvested	13,055		13,055		13,055	8,100
Restricted shares vested during period			2,990		2,115
Allocated share-based compensation expense	$ 19,000	$ 8,000	$ 37,000	$ 17,000	$ 53,000	$ 28,000
Dividend Reinvestment Plan [Member]
Class of Stock [Line Items]
Shares authorized per plan					330,750

Common Stock (Schedule of Compe

Common Stock (Schedule of Compensation Expense and Related Tax Benefits for Restricted Stock Awards Recognized) (Detail) - 2014 Restricted Stock Plan [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense	$ 19	$ 8	$ 37	$ 17	$ 53	$ 28
Income tax benefit					(18)	(10)
Net income effect					$ 35	$ 18

Common Stock (Schedule of Non-V

Common Stock (Schedule of Non-Vested Restricted Stock) (Detail) - 2014 Restricted Stock Plan [Member] - $ / shares	6 Months Ended	12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares, Non-vested at January 1, 2016	13,055	8,100
Shares, Vested	(2,990)	(2,115)
Shares, Cancelled		(470)
Shares, Granted	16,045	7,540	5,475	3,500
Shares, Non-vested at December 31, 2016	13,055	13,055	8,100
Weighted-Average Grant Date Fair Value, Non-vested at January 1, 2016	$ 17.66	$ 16.13
Weighted-Average Grant Date Fair Value, Vested		16.10
Weighted-Average Grant Date Fair Value, Cancelled		16.09
Weighted-Average Grant Date Fair Value, Granted		18.77
Weighted-Average Grant Date Fair Value, Non-vested at December 31, 2016		$ 17.66	$ 16.13

Preferred Stock (Small Business

Preferred Stock (Small Business Lending Fund) (Narrative) (Detail) - USD ($)	Jan. 19, 2016	Dec. 15, 2015	Dec. 09, 2015	Jan. 03, 2013	Dec. 31, 2015	Mar. 01, 2015
Phoenix Bancorp Inc. [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued						1,750
Preferred Class B [Member]
Class of Stock [Line Items]
Preferred Stock, Dividend Rate, Percentage				7.00%
Payments for Repurchase of Redeemable Preferred Stock			$ 5,123,000
Stock issued during period, shares, new issues				5,000
Proceeds from issuance of private placement				$ 5,000,000
Preferred stock, redemption price per share			$ 1,024.67
Preferred Stock Redemption Price Per Share Excluding Dividends Declared But Unpaid			$ 1,020
Series C Preferred Stock [Member]
Class of Stock [Line Items]
Preferred Stock, Dividend Rate, Percentage	1.00%
Payments for Repurchase of Redeemable Preferred Stock		$ 1,754,000			$ 1,750,000
Preferred Stock, Shares Issued						1,750
Preferred Stock, Liquidation Preference Per Share						$ 1,000
Series C Preferred Stock [Member] | Phoenix Bancorp Inc. [Member]
Class of Stock [Line Items]
Preferred Stock, Shares Issued						1,750
Preferred Stock, Liquidation Preference Per Share						$ 1,000

Parent Company Statements (Cond

Parent Company Statements (Condensed Balance Sheets) (Detail) - USD ($)	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash and cash equivalents	$ 29,179,000	$ 45,973,000	$ 40,960,000	$ 13,284,000	$ 9,882,000	$ 8,623,000
Investment in subsidiaries		321,000		365,000
Other assets	3,408,000	3,215,000		3,116,000
Total Assets	1,111,876,000	1,032,599,000		931,638,000
Subordinated debt	7,419,000	7,414,000		7,414,000
Other liabilities	5,630,000	5,249,000		4,822,000
Shareholders' equity	75,636,000	70,467,000	$ 74,474,000	70,068,000	59,130,000	52,916,000
Total Liabilities and Shareholders' Equity	$ 1,111,876,000	1,032,599,000		931,638,000
Parent Company [Member]
Cash and cash equivalents		780,000		564,000	$ 554,000	$ 437,000
Equity investments		545,000		626,000
Investment in subsidiaries		77,029,000		76,334,000
Other assets		40,000		14,000
Total Assets		78,394,000		77,538,000
Subordinated debt		7,414,000		7,414,000
Other liabilities		513,000		56,000
Shareholders' equity		70,467,000		70,068,000
Total Liabilities and Shareholders' Equity		$ 78,394,000		$ 77,538,000

Parent Company Statements (C117

Parent Company Statements (Condensed Statement of Income and Comprehensive Income) (Detail) - USD ($) $ in Thousands	3 Months Ended									6 Months Ended		12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Other expenses	$ (1,215)			$ (1,074)						$ (2,334)	$ (2,095)	$ (4,683)	$ (4,122)	$ (3,304)
Income before income tax and equity in undistributed earnings (loss) of subsidiaries	3,114	$ 2,714	$ 2,427	2,615	$ 2,325	$ 2,048	$ 2,440	$ 2,637	$ 1,047	5,798	4,940	10,081	8,172	7,163
Income tax benefit	(769)	(638)	(526)	(593)	(520)	(421)	(546)	(593)	(84)	(1,459)	(1,113)	(2,277)	(1,644)	(1,462)
NET INCOME	2,345			2,022		1,627	1,894	2,044	963	4,339	3,827	7,804	6,528	5,701
NET INCOME AVAILABLE TO COMMON SHAREHOLDERS		$ 2,076	$ 1,901	2,022	$ 1,805	1,408	1,802	1,952	876			7,804	6,038	5,351
Comprehensive income	$ 3,816			$ 3,734						$ 6,181	$ 5,791	3,139	6,827	8,086
Series B Preferred Stock [Member]
Preferred stock dividends and redemption premium						210	88	88	$ 87				473	350
Preferred stock dividends													373	350
Series C Preferred Stock [Member]
Preferred stock dividends						$ 9	$ 4	$ 4					17
Parent Company [Member]
Dividends from subsidiaries												2,871	5,662	2,325
Other income												33	19
Total Income												2,904	5,681	2,325
Other expenses												(606)	(695)	(716)
Total Expense												(606)	(695)	(716)
Income before income tax and equity in undistributed earnings (loss) of subsidiaries												2,298	4,986	1,609
Equity in undistributed earnings (loss) of subsidiaries												5,311	1,346	4,012
Income before income tax												7,609	6,332	5,621
Income tax benefit												195	196	80
NET INCOME												7,804	6,528	5,701
NET INCOME AVAILABLE TO COMMON SHAREHOLDERS												7,804	6,038	5,351
Comprehensive income												$ 3,139	6,827	8,086
Parent Company [Member] | Series B Preferred Stock [Member]
Preferred stock dividends and redemption premium													473	$ 350
Parent Company [Member] | Series C Preferred Stock [Member]
Preferred stock dividends													$ 17

Parent Company Statements (C118

Parent Company Statements (Condensed Statement of Cash Flows) (Detail) - USD ($)	Dec. 15, 2015	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net income		$ 2,345,000	$ 2,022,000	$ 1,627,000	$ 1,894,000	$ 2,044,000	$ 963,000	$ 4,339,000	$ 3,827,000	$ 7,804,000	$ 6,528,000	$ 5,701,000
Decrease (increase) in other assets								(193,000)	161,000	(99,000)	333,000	(547,000)
Increase (decrease) in other liabilities								381,000	1,847,000	427,000	(771,000)	9,000
Net cash provided by operating activities								4,513,000	18,786,000	22,271,000	13,174,000	8,670,000
Net cash used in investing activities								(93,712,000)	(64,393,000)	(86,799,000)	(38,903,000)	(41,892,000)
Dividends paid								(1,101,000)	(1,437,000)	(2,875,000)	(1,785,000)	(1,575,000)
Employee Stock Purchase Plan								52,000	35,000	82,000	66,000	53,000
Deferred financing fees paid for subordinated debt issuance											(85,000)
Subordinated debt issuance											7,500,000
Net Cash Provided By Financing Activities								72,405,000	73,283,000	97,217,000	29,131,000	34,481,000
Net increase in cash and cash equivalents								(16,794,000)	27,676,000	32,689,000	3,402,000	1,259,000
Cash and cash equivalents, beginning of period							9,882,000	45,973,000	13,284,000	13,284,000	9,882,000	8,623,000
Cash and cash equivalents, end of period		$ 29,179,000	$ 40,960,000	13,284,000				29,179,000	40,960,000	45,973,000	13,284,000	9,882,000
Series B Preferred Stock [Member]
Preferred stock redemption											(5,000,000)
Series C Preferred Stock [Member]
Preferred stock redemption	$ (1,754,000)										(1,750,000)
Parent Company [Member]
Net income										7,804,000	6,528,000	5,701,000
Equity in undistributed earnings (loss) of subsidiaries										(5,311,000)	(1,346,000)	(4,012,000)
Decrease (increase) in other assets										59,000	(14,000)	8,000
Increase (decrease) in other liabilities										457,000	(665,000)	292,000
Net cash provided by operating activities										3,009,000	4,503,000	1,989,000
Net cash paid for acquisition											(2,949,000)
Net cash used in investing activities											(2,949,000)
Dividends paid										(2,875,000)	(2,175,000)	(1,925,000)
Employee Stock Purchase Plan										82,000	66,000	53,000
Deferred financing fees paid for subordinated debt issuance											(85,000)
Subordinated debt issuance											7,500,000
Net Cash Provided By Financing Activities										(2,793,000)	(1,544,000)	(1,872,000)
Net increase in cash and cash equivalents										216,000	10,000	117,000
Cash and cash equivalents, beginning of period							$ 554,000	$ 780,000	$ 564,000	564,000	554,000	437,000
Cash and cash equivalents, end of period				$ 564,000						$ 780,000	564,000	$ 554,000
Parent Company [Member] | Series B Preferred Stock [Member]
Preferred stock redemption premium											(100,000)
Preferred stock redemption											(5,000,000)
Parent Company [Member] | Series C Preferred Stock [Member]
Preferred stock redemption											$ (1,750,000)

Recent Accounting Pronouncem119

Recent Accounting Pronouncements (Narrative) (Detail) - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Accounting Changes and Error Corrections [Abstract]
Equity investments (excluding restricted investments in bank stocks)	$ 1,171,000	$ 2,156,000

Summary of Quarterly Consoli120

Summary of Quarterly Consolidated Financial Data (Unaudited) (Quarterly Condensed Financials) (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended									6 Months Ended		12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Interest Income	$ 10,879	$ 10,531	$ 10,125	$ 9,859	$ 9,697	$ 9,349	$ 9,339	$ 9,644	$ 8,158	$ 21,438	$ 19,556	$ 40,212	$ 36,490	$ 30,627
Interest Expense	1,469	1,402	1,367	1,326	1,282	1,179	1,150	1,158	1,120	2,853	2,608	5,367	4,607	4,427
Net Interest Income	9,410	9,129	8,758	8,533	8,415	8,170	8,189	8,486	7,038	18,585	16,948	34,845	31,883	26,200
Provision for Loan and Lease Losses	100	550	585	395	340	200	265	300	300	225	735	1,870	1,065	1,617
Net Interest Income After Provision for Loan Losses	9,310	8,579	8,173	8,138	8,075	7,970	7,924	8,186	6,738	18,360	16,213	32,975	30,818	24,583
Noninterest Income	1,362	1,875	1,419	1,398	1,232	960	1,085	1,093	949	2,798	2,630	5,924	4,113	3,284
Noninterest expense	7,558	7,740	7,165	6,921	6,982	6,882	6,569	6,642	6,640	15,360	13,903	28,818	26,759	20,704
INCOME BEFORE PROVISION FOR INCOME TAXES	3,114	2,714	2,427	2,615	2,325	2,048	2,440	2,637	1,047	5,798	4,940	10,081	8,172	7,163
Provision for Income Taxes	769	638	526	593	520	421	546	593	84	1,459	1,113	2,277	1,644	1,462
Net income	$ 2,345			2,022		1,627	1,894	2,044	963	$ 4,339	$ 3,827	7,804	6,528	5,701
NET INCOME AVAILABLE TO COMMON SHAREHOLDERS		$ 2,076	$ 1,901	$ 2,022	$ 1,805	$ 1,408	$ 1,802	$ 1,952	$ 876			$ 7,804	$ 6,038	$ 5,351
Basic earnings per common share	$ 0.55	$ 0.49	$ 0.45	$ 0.48	$ 0.43	$ 0.35	$ 0.43	$ 0.46	$ 0.23	$ 1.02	$ 0.91	$ 1.85	$ 1.47	$ 1.53
Cash Dividends Declared		$ 0.22	$ 0.12	$ 0.12	$ 0.22	$ 0.12	$ 0.12	$ 0.10	$ 0.10			$ 0.68	$ 0.44	$ 0.45
Scenario, Previously Reported [Member]
Interest Expense				$ 1,316
Net Interest Income				8,543
Net Interest Income After Provision for Loan Losses				8,148
Noninterest expense				$ 6,931
Series B Preferred Stock [Member]
Preferred stock dividends and redemption premium						$ 210	$ 88	$ 88	$ 87				$ 473	$ 350
Preferred stock dividends													373	$ 350
Series C Preferred Stock [Member]
Preferred stock dividends						$ 9	$ 4	$ 4					$ 17

Guarantees and Commitments (Nar

Guarantees and Commitments (Narrative) (Detail)	6 Months Ended	12 Months Ended
	Jun. 30, 2017USD ($)Property	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Commitments Contingencies And Guarantees [Line Items]
Concentration Risk, Credit Risk, Financial Instrument, Maximum Exposure		$ 201,749,000	$ 157,338,000
Fixed asset acquisition commitments settlement payment date	2017-07
Harrisburg, PA [Member] | Commercial Building [Member]
Commitments Contingencies And Guarantees [Line Items]
Fixed asset acquisition commitments	$ 2,100,000
Harrisburg, PA [Member] | Vacant and Undeveloped Lots Adjacent to Commercial Building [Member]
Commitments Contingencies And Guarantees [Line Items]
Fixed asset acquisition commitments	$ 462,000
Number of fixed asset purchased | Property	2
Halifax, PA [Member] | Land [Member]
Commitments Contingencies And Guarantees [Line Items]
Fixed asset acquisition commitments	$ 504,000
Financial Standby Letters of Credit [Member]
Commitments Contingencies And Guarantees [Line Items]
Concentration Risk, Credit Risk, Financial Instrument, Maximum Exposure	$ 23,595,000	$ 14,000,000

Defined Benefit Plans - Net Per

Defined Benefit Plans - Net Periodic Benefit Costs (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service Cost	$ 9	$ 8	$ 18	$ 17
Interest Cost	11	11	22	23
Amortization (accretion) of prior service cost	4	8	7	25
Net periodic benefit cost	24	27	47	65
Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service Cost	1	1	2	2
Interest Cost	5	5	10	11
Amortization (accretion) of prior service cost	$ (6)	6	$ (12)	91
Net periodic benefit cost		$ 12		$ 104

Earnings per Common Share (Basi

Earnings per Common Share (Basic Earnings (Loss) Per Share) (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended									6 Months Ended		12 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share [Abstract]
Net income	$ 2,345			$ 2,022		$ 1,627	$ 1,894	$ 2,044	$ 963	$ 4,339	$ 3,827	$ 7,804	$ 6,528	$ 5,701
Weighted average common shares outstanding	4,234,291			4,227,992						4,234,525	4,227,362	4,229,284	4,106,548	3,495,705
Basic earnings per common share	$ 0.55	$ 0.49	$ 0.45	$ 0.48	$ 0.43	$ 0.35	$ 0.43	$ 0.46	$ 0.23	$ 1.02	$ 0.91	$ 1.85	$ 1.47	$ 1.53

Earnings per Common Share (B124

Earnings per Common Share (Basic Earnings (Loss) Per Share) (Narrative) (Detail) - shares	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share [Abstract]
Class of warrant or right, outstanding	0	0	0	0	0

Agreement and Plan of Merger (N

Agreement and Plan of Merger (Narrative) (Detail) - Scottdale Bank and Trust Company [Member]	Mar. 29, 2017$ / shares
Business Acquisition [Line Items]
Per share price	$ 1,166
Volume-weighted average price, trading period	10 days
Period prior to closing of merger for calculating Average Price	5 days
Percentage of outstanding shares of acquiree's common stock to be converted into right to receive shares of acquirer's common stock upon merger	90.00%
Percentage of outstanding shares of acquiree's common stock to be converted into right to receive shares of acquirer's common stock in event that shareholders perfecting dissenters' rights upon merger	85.00%
Percentage of outstanding shares of acquiree's common stock that perfect shareholders' dissenters rights	15.00%
Minimum [Member]
Business Acquisition [Line Items]
Merger agreement exchange ratio	38.88%
Maximum [Member]
Business Acquisition [Line Items]
Merger agreement exchange ratio	44.86%
Percentage of outstanding shares of acquiree's common stock that perfect shareholders' dissenters rights	15.00%