Donegal (DGICA) 10-Q 8 Aug 17 2017 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2017	Aug. 01, 2017
Document Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q2
Trading Symbol	DGICA
Entity Registrant Name	Donegal Group Inc.
Entity Central Index Key	800,457
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Class A Common Stock [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		21,745,343
Class B Common Stock [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		5,576,775

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Fixed maturities
Held to maturity, at amortized cost	$ 356,306,558	$ 336,100,948
Available for sale, at fair value	511,309,135	515,074,940
Equity securities, available for sale, at fair value	46,315,737	47,087,842
Investment in affiliate	38,849,498	37,884,918
Short-term investments, at cost, which approximates fair value	32,152,315	9,371,007
Total investments	984,933,243	945,519,655
Cash	28,840,928	24,587,214
Accrued investment income	6,214,412	6,295,513
Premiums receivable	170,978,478	159,389,667
Reinsurance receivable	277,174,457	263,028,008
Deferred policy acquisition costs	61,079,078	56,309,196
Deferred tax asset, net	19,146,320	19,043,413
Prepaid reinsurance premiums	136,936,723	124,255,495
Property and equipment, net	6,707,754	6,668,489
Accounts receivable - securities	325,000
Federal income taxes receivable	3,146,481	1,108,250
Due from affiliate		9,204,910
Goodwill	5,625,354	5,625,354
Other intangible assets	958,010	958,010
Other	1,214,940	1,137,863
Total assets	1,703,281,178	1,623,131,037
Liabilities
Unpaid losses and loss expenses	643,246,130	606,664,590
Unearned premiums	509,838,037	466,055,228
Accrued expenses	22,436,301	28,246,691
Reinsurance balances payable	6,286,597	4,369,528
Borrowings under lines of credit	69,000,000	69,000,000
Cash dividends declared to stockholders		3,622,821
Subordinated debentures	5,000,000	5,000,000
Accounts payable - securities	272,766
Due to affiliate	2,576,949
Other	1,492,332	1,556,859
Total liabilities	1,260,149,112	1,184,515,717
Stockholders' Equity
Preferred stock, $.01 par value, authorized 2,000,000 shares; none issued
Additional paid-in capital	241,909,842	236,851,709
Accumulated other comprehensive loss	(1,551,482)	(2,254,271)
Retained earnings	243,696,348	244,942,913
Treasury stock, at cost	(41,226,357)	(41,226,357)
Total stockholders' equity	443,132,066	438,615,320
Total liabilities and stockholders' equity	1,703,281,178	1,623,131,037
Class A Common Stock [Member]
Stockholders' Equity
Common stock value	247,223	244,834
Total stockholders' equity	247,223	244,834
Class B Common Stock [Member]
Stockholders' Equity
Common stock value	56,492	56,492
Total stockholders' equity	$ 56,492	$ 56,492

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2017	Dec. 31, 2016
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	2,000,000	2,000,000
Preferred stock, shares issued	0	0
Class A Common Stock [Member]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	40,000,000	40,000,000
Common stock, shares issued	24,722,276	24,483,377
Common stock, shares outstanding	21,719,688	21,480,789
Class B Common Stock [Member]
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	5,649,240	5,649,240
Common stock, shares outstanding	5,576,775	5,576,775

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenues:
Net premiums earned	$ 175,014,872	$ 161,942,637	$ 344,171,019	$ 320,417,916
Investment income, net of investment expenses	5,649,870	5,343,883	11,405,269	10,890,392
Net realized investment gains	1,097,306	715,177	3,646,281	1,186,118
Lease income	127,924	172,629	269,774	350,989
Installment payment fees	1,304,129	1,367,066	2,439,771	2,729,526
Equity in earnings of Donegal Financial Services Corporation	386,615	305,475	619,565	340,702
Total revenues	183,580,716	169,846,867	362,551,679	335,915,643
Expenses:
Net losses and loss expenses	128,005,914	103,193,915	242,439,372	198,771,980
Amortization of deferred policy acquisition costs	28,700,000	26,554,000	56,383,000	52,510,000
Other underwriting expenses	28,259,223	26,578,997	56,748,504	53,217,024
Policyholder dividends	1,212,292	754,682	2,046,557	1,586,569
Interest	382,958	403,882	746,633	812,362
Other expenses	416,798	315,699	859,253	953,477
Total expenses	186,977,185	157,801,175	359,223,319	307,851,412
(Loss) income before income tax (benefit) expense	(3,396,469)	12,045,692	3,328,360	28,064,231
Income tax (benefit) expense	(1,077,821)	3,461,038	542,190	7,630,664
Net (loss) income	$ (2,318,648)	$ 8,584,654	$ 2,786,170	$ 20,433,567
Class A Common Stock [Member]
(Loss) earnings per common share:
Common stock - basic	$ (0.09)	$ 0.33	$ 0.11	$ 0.79
Common stock - diluted	(0.08)	0.32	0.10	0.78
Class B Common Stock [Member]
(Loss) earnings per common share:
Common stock - basic	(0.08)	0.30	0.09	0.72
Common stock - diluted	(0.08)	0.30	0.09	0.72
Common stock - basic and diluted	$ (0.08)	$ 0.30	$ 0.09	$ 0.72

Consolidated Statements of Inc5

Consolidated Statements of Income (Parenthetical) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Net realized investment gains	$ 1,097,306	$ 715,177	$ 3,646,281	$ 1,186,118
Income tax (benefit) expense	(1,077,821)	3,461,038	542,190	7,630,664
Reclassification out of Accumulated Other Comprehensive Income [Member]
Net realized investment gains	1,097,306	715,177	3,646,281	1,186,118
Income tax (benefit) expense	$ 384,057	$ 250,312	$ 1,276,198	$ 415,141

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (2,318,648)	$ 8,584,654	$ 2,786,170	$ 20,433,567
Unrealized gain on securities:
Unrealized holding gain during the period, net of income tax expense	1,069,259	3,840,822	3,072,872	8,105,840
Reclassification adjustment for gains included in net income, net of income tax expense	(713,249)	(464,865)	(2,370,083)	(770,977)
Other comprehensive income	356,010	3,375,957	702,789	7,334,863
Comprehensive (loss) income	$ (1,962,638)	$ 11,960,611	$ 3,488,959	$ 27,768,430

Consolidated Statements of Com7

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Income tax expense on unrealized holding gain arising during the period	$ 575,754	$ 2,068,136	$ 1,654,622	$ 4,364,683
Income tax expense on reclassification adjustment for gains	$ 384,057	$ 250,312	$ 1,276,198	$ 415,141

Consolidated Statement of Stock

Consolidated Statement of Stockholders' Equity - 6 months ended Jun. 30, 2017 - USD ($)	Total	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Class A Common Stock [Member]	Class B Common Stock [Member]
Balance at Dec. 31, 2016	$ 438,615,320	$ 236,851,709	$ (2,254,271)	$ 244,942,913	$ (41,226,357)	$ 244,834	$ 56,492
Balance, shares at Dec. 31, 2016						24,483,377	5,649,240
Issuance of common stock	1,354,310	1,353,489				$ 821
Issuance of common stock, shares						82,068
Share-based compensation	3,402,316	3,400,748				$ 1,568
Share-based compensation, shares						156,831
Net income	2,786,170			2,786,170
Cash dividends declared	(3,728,839)			(3,728,839)
Grant of stock options		303,896		(303,896)
Other comprehensive income	702,789		702,789
Balance at Jun. 30, 2017	$ 443,132,066	$ 241,909,842	$ (1,551,482)	$ 243,696,348	$ (41,226,357)	$ 247,223	$ 56,492
Balance, shares at Jun. 30, 2017						24,722,276	5,649,240

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash Flows from Operating Activities:
Net income	$ 2,786,170	$ 20,433,567
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and other non-cash items	3,399,601	3,793,569
Net realized investment gains	(3,646,281)	(1,186,118)
Equity in earnings of Donegal Financial Services Corporation	(619,565)	(340,702)
Changes in assets and liabilities:
Losses and loss expenses	36,581,540	(1,040,106)
Unearned premiums	43,782,809	41,524,677
Premiums receivable	(11,588,811)	(18,723,440)
Deferred acquisition costs	(4,769,882)	(4,235,656)
Deferred income taxes	(481,330)	1,368,719
Reinsurance receivable	(14,146,449)	1,588,116
Prepaid reinsurance premiums	(12,681,228)	(13,632,529)
Accrued investment income	81,101	33,545
Due to affiliate	11,781,859	1,408,894
Reinsurance balances payable	1,917,069	438,358
Current income taxes	(2,038,231)	842,019
Accrued expenses	(5,810,390)	(3,292,693)
Other, net	(141,602)	(1,473,961)
Net adjustments	41,620,210	7,072,692
Net cash provided by operating activities	44,406,380	27,506,259
Cash Flows from Investing Activities:
Purchases of fixed maturities, held to maturity	(30,889,730)	(27,292,675)
Purchases of fixed maturities, available for sale	(42,607,193)	(98,008,601)
Purchases of equity securities, available for sale	(6,888,091)	(5,604,316)
Maturity of fixed maturities:
Held to maturity	10,695,775	9,540,543
Available for sale	42,557,614	55,080,426
Sales of fixed maturities, available for sale	3,373,785	40,206,225
Sales of equity securities, available for sale	10,782,859	1,416,252
Net purchases of property and equipment	(302,622)	(162,153)
Net (purchases) sales of short-term investments	(22,781,308)	4,043,472
Net cash used in investing activities	(36,058,911)	(20,780,827)
Cash Flows from Financing Activities:
Cash dividends paid	(7,351,660)	(6,937,914)
Issuance of common stock	3,257,905	5,269,989
Payment on lines of credit		(3,500,000)
Net cash used in financing activities	(4,093,755)	(5,167,925)
Net increase in cash	4,253,714	1,557,507
Cash at beginning of period	24,587,214	28,139,144
Cash at end of period	28,840,928	29,696,651
Cash paid during period - Interest	616,562	648,705
Net cash paid during period - Taxes	$ 3,050,000	$ 6,055,000

Organization

Organization	6 Months Ended
	Jun. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	1 - Organization Donegal Mutual Insurance Company (“Donegal Mutual”) organized us as an insurance holding company on August 26, 1986. Our insurance subsidiaries, Atlantic States Insurance Company (“Atlantic States”), Southern Insurance Company of Virginia (“Southern”), Le Mars Insurance Company (“Le Mars”), the Peninsula Insurance Group (“Peninsula”), which consists of Peninsula Indemnity Company and The Peninsula Insurance Company, Sheboygan Falls Insurance Company (“Sheboygan”) and Michigan Insurance Company (“MICO”), write personal and commercial lines of property and casualty coverages exclusively through independent insurance agents in certain Mid-Atlantic, Midwestern, New England and Southern states. We also own 48.2% of the outstanding stock of Donegal Financial Services Corporation (“DFSC”), a grandfathered unitary savings and loan holding company that owns Union Community Bank (“UCB”), a state savings bank. Donegal Mutual owns the remaining 51.8% of the outstanding stock of DFSC. We have four segments: our investment function, our personal lines of insurance, our commercial lines of insurance and our investment in DFSC. The personal lines products of our insurance subsidiaries consist primarily of homeowners and private passenger automobile policies. The commercial lines products of our insurance subsidiaries consist primarily of commercial automobile, commercial multi-peril and workers’ compensation policies. At June 30, 2017, Donegal Mutual held approximately 45% of our outstanding Class A common stock and approximately 83% of our outstanding Class B common stock. That ownership provides Donegal Mutual with approximately 73% of the combined voting power of our outstanding shares of Class A common stock and our outstanding shares of Class B common stock. We believe Donegal Mutual’s voting control of us benefits us for the reasons we describe in our Annual Reports on Form 10-K and in our proxy statements. Our insurance subsidiaries and Donegal Mutual have interrelated operations due to a pooling agreement and other intercompany agreements and transactions. While each company maintains its separate corporate existence, Donegal Mutual and our insurance subsidiaries conduct business together as the Donegal Insurance Group. As such, Donegal Mutual and our insurance subsidiaries share the same business philosophy, the same management, the same employees and the same facilities and offer the same types of insurance products. Atlantic States, our largest subsidiary, participates in a pooling agreement with Donegal Mutual. Under the pooling agreement, Donegal Mutual and Atlantic States pool their insurance business and each company receives an allocated percentage of the pooled business. Atlantic States has an 80% share of the results of the pooled business, and Donegal Mutual has a 20% share of the results of the pooled business. Pooled business represents the predominant percentage of the net underwriting activity of both Donegal Mutual and Atlantic States. Donegal Mutual completed the merger of Mountain States Mutual Casualty Company (“Mountain States”) with and into Donegal Mutual effective May 25, 2017. Donegal Mutual is the surviving company in the merger, and Mountain States’ insurance subsidiaries, Mountain States Indemnity Company and Mountain States Commercial Insurance Company, became insurance subsidiaries of Donegal Mutual as a result of the merger. As of the effective date of the merger, Donegal Mutual assumed all of the policy obligations of Mountain States and began to market its products together with its insurance subsidiaries as the Mountain States Insurance Group in certain Southwestern states. For an indefinite period of time, Donegal Mutual will exclude the business of the Mountain States Insurance Group from the pooling agreement with Atlantic States. As a result, our consolidated financial results will exclude the results of Donegal Mutual’s operations in those Southwestern states. The same executive management and underwriting personnel administer products, classes of business underwritten, pricing practices and underwriting standards of Donegal Mutual and our insurance subsidiaries. In addition, as the Donegal Insurance Group, Donegal Mutual and our insurance subsidiaries share a combined business plan to achieve market penetration and underwriting profitability objectives. The products our insurance subsidiaries and Donegal Mutual market are generally complementary, thereby allowing the Donegal Insurance Group to offer a broader range of products to a given market and to expand the Donegal Insurance Group’s ability to service entire personal lines or commercial lines accounts. Distinctions within the products Donegal Mutual and our insurance subsidiaries offer relate generally to specific risk profiles targeted within similar classes of business, such as preferred tier products versus standard tier products, but we do not allocate all of the standard risk gradients to one company. Therefore, the underwriting profitability of the business the individual companies write directly will vary. However, because the risk characteristics of all business Donegal Mutual and Atlantic States write directly are homogenized within the underwriting pool, Donegal Mutual and Atlantic States share the underwriting results in proportion to their respective participation in the underwriting pool. On July 18, 2013, our board of directors authorized a share repurchase program pursuant to which we have the authority to purchase up to 500,000 shares of our Class A common stock at prices prevailing from time to time in the open market subject to the provisions of applicable rules of the SEC and in privately negotiated transactions. We did not purchase any shares of our Class A common stock under this program during the six months ended June 30, 2017 or 2016 . We have purchased a total of 57,658 shares of our Class A common stock under this program from its inception through June 30, 2017.

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	2 - Basis of Presentation Our financial information for the interim periods included in this Form 10-Q Report is unaudited; however, our financial information we include in this Form 10-Q Report reflects all adjustments, consisting only of normal recurring adjustments that, in the opinion of our management, are necessary for a fair presentation of our financial position, results of operations and cash flows for those interim periods. Our results of operations for the six months ended June 30, 2017 are not necessarily indicative of the results of operations we expect for the year ending December 31, 2017. We recommend you read the interim financial statements we include in this Form 10-Q Report in conjunction with the financial statements and the notes to our financial statements contained in our Annual Report on Form 10-K for the year ended December 31, 2016.

Earnings Per Share

Earnings Per Share	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Earnings Per Share	3 - Earnings Per Share We have two classes of common stock, which we refer to as our Class A common stock and our Class B common stock. Our certificate of incorporation provides that whenever our board of directors declares a dividend on our Class B common stock, our board of directors shall simultaneously declare a dividend on our Class A common stock that is payable to the holders of our Class A common stock at the same time and as of the same record date at a rate that is at least 10% greater than the rate at which our board of directors declared a dividend on our Class B common stock. Accordingly, we use the two-class method to compute our earnings per common share. The two-class method is an earnings allocation formula that determines earnings per share separately for each class of common stock based on dividends we have declared and an allocation of our remaining undistributed earnings using a participation percentage that reflects the dividend rights of each class. The table below presents for the periods indicated a reconciliation of the numerators and denominators we used to compute basic and diluted net (loss) income per share for each class of our common stock: Three Months Ended June 30, 2017 2016 Class A Class B Class A Class B (in thousands, except per share data) Basic net (loss) income per share: Numerator: Allocation of net (loss) income $ (1,858 ) $ (461 ) $ 6,919 $ 1,666 Denominator: Weighted-average shares outstanding 21,705 5,577 20,746 5,577 Basic net (loss) income per share $ (0.09 ) $ (0.08 ) $ 0.33 $ 0.30 Diluted net (loss) income per share: Numerator: Allocation of net (loss) income $ (1,858 ) $ (461 ) $ 6,919 $ 1,666 Denominator: Number of shares used in basic computation 21,705 5,577 20,746 5,577 Weighted-average shares effect of dilutive securities Add: Director and employee stock options 792 — 576 — Number of shares used in diluted computation 22,497 5,577 21,322 5,577 Diluted net (loss) income per share $ (0.08 ) $ (0.08 ) $ 0.32 $ 0.30 Six Months Ended June 30, 2017 2016 Class A Class B Class A Class B (in thousands, except per share data) Basic net income per share: Numerator: Allocation of net income $ 2,282 $ 504 $ 16,412 $ 4,022 Denominator: Weighted-average shares outstanding 21,625 5,577 20,645 5,577 Basic net income per share $ 0.11 $ 0.09 $ 0.79 $ 0.72 Diluted net income per share: Numerator: Allocation of net income $ 2,282 $ 504 $ 16,412 $ 4,022 Denominator: Number of shares used in basic computation 21,625 5,577 20,645 5,577 Weighted-average shares effect of dilutive securities Add: Director and employee stock options 937 — 424 — Number of shares used in diluted computation 22,562 5,577 21,069 5,577 Diluted net income per share $ 0.10 $ 0.09 $ 0.78 $ 0.72 We did not include outstanding options to purchase the following number of shares of Class A common stock in our computation of diluted earnings per share because the exercise price of the options exceeded the average market price of our Class A common stock during the applicable periods: Three Months Six Months Ended 2017 2016 2017 2016 Number of options to purchase Class A shares excluded 1,388,400 — 1,388,400 —

Reinsurance

Reinsurance	6 Months Ended
	Jun. 30, 2017
Insurance [Abstract]
Reinsurance	4 - Reinsurance Atlantic States and Donegal Mutual have participated in a pooling agreement since 1986 under which each company places all of its direct written premiums into the pool the pooling agreement established, and Atlantic States and Donegal Mutual then share the underwriting results of the pool in accordance with the terms of the pooling agreement. Atlantic States has an 80% share of the results of the pool, and Donegal Mutual has a 20% share of the results of the pool. Our insurance subsidiaries and Donegal Mutual purchase certain third-party reinsurance on a combined basis. Le Mars, MICO, Peninsula and Sheboygan also purchase separate third-party reinsurance that provides coverage that we believe is commensurate with their relative size and risk exposures. Our insurance subsidiaries use several different reinsurers, all of which, consistent with the requirements of our insurance subsidiaries and Donegal Mutual, have an A.M. Best rating of A- (Excellent) or better or, with respect to foreign reinsurers, have a financial condition that, in the opinion of our management, is equivalent to a company with at least an A- rating from A.M. Best. The following information describes the external reinsurance our insurance subsidiaries have in place for 2017: • excess of loss reinsurance, under which Donegal Mutual and our insurance subsidiaries recover, through a series of reinsurance agreements, losses over a set retention (generally $1.0 million), and • catastrophe reinsurance, under which Donegal Mutual and our insurance subsidiaries recover, through a series of reinsurance agreements, 100% of an accumulation of many losses resulting from a single event, including natural disasters, over a set retention (generally $5.0 million) and after exceeding an annual aggregate deductible (generally $1.0 million) up to aggregate losses of $170.0 million per occurrence. Our insurance subsidiaries and Donegal Mutual also purchase facultative reinsurance to cover exposures in excess of the covered limits of their third-party reinsurance agreements. In addition to the pooling agreement and third-party reinsurance, our insurance subsidiaries have various reinsurance agreements with Donegal Mutual. We have made no significant changes to our third-party reinsurance or the reinsurance agreements between our insurance subsidiaries and Donegal Mutual during the six months ended June 30, 2017.

Investments

Investments	6 Months Ended
	Jun. 30, 2017
Investments, Debt and Equity Securities [Abstract]
Investments	5 - Investments The amortized cost and estimated fair values of our fixed maturities and equity securities at June 30, 2017 were as follows: Amortized Gross Gross Estimated (in thousands) Held to Maturity U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 65,104 $ 1,454 $ 497 $ 66,061 Obligations of states and political subdivisions 133,149 10,574 195 143,528 Corporate securities 103,305 2,338 1,287 104,356 Mortgage-backed securities 54,749 804 83 55,470 Totals $ 356,307 $ 15,170 $ 2,062 $ 369,415 Amortized Gross Gross Estimated (in thousands) Available for Sale U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 39,186 $ 85 $ 437 $ 38,834 Obligations of states and political subdivisions 157,048 5,582 204 162,426 Corporate securities 93,225 1,060 442 93,843 Mortgage-backed securities 217,734 744 2,272 216,206 Fixed maturities 507,193 7,471 3,355 511,309 Equity securities 42,163 4,875 722 46,316 Totals $ 549,356 $ 12,346 $ 4,077 $ 557,625 At June 30, 2017, our holdings of obligations of states and political subdivisions included general obligation bonds with an aggregate fair value of $209.9 million and an amortized cost of $199.7 million. Our holdings at June 30, 2017 also included special revenue bonds with an aggregate fair value of $96.1 million and an amortized cost of $90.5 million. With respect to both categories of those bonds at June 30, 2017, we held no securities of any issuer that comprised more than 10% of our holdings of either bond category. Education bonds and water and sewer utility bonds represented 58% and 23%, respectively, of our total investments in special revenue bonds based on the carrying values of these investments at June 30, 2017. Many of the issuers of the special revenue bonds we held at June 30, 2017 have the authority to impose ad valorem taxes. In that respect, many of the special revenue bonds we held at June 30, 2017 were similar to general obligation bonds. The amortized cost and estimated fair values of our fixed maturities and equity securities at December 31, 2016 were as follows: Amortized Gross Gross Estimated (in thousands) Held to Maturity U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 61,382 $ 1,255 $ 674 $ 61,963 Obligations of states and political subdivisions 122,793 8,404 369 130,828 Corporate securities 91,555 1,172 1,678 91,049 Mortgage-backed securities 60,371 546 110 60,807 Totals $ 336,101 $ 11,377 $ 2,831 $ 344,647 Amortized Gross Gross Estimated (in thousands) Available for Sale U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 39,094 $ 100 $ 606 $ 38,588 Obligations of states and political subdivisions 179,889 6,637 443 186,083 Corporate securities 87,715 662 921 87,456 Mortgage-backed securities 204,931 637 2,620 202,948 Fixed maturities 511,629 8,036 4,590 515,075 Equity securities 42,432 4,788 132 47,088 Totals $ 554,061 $ 12,824 $ 4,722 $ 562,163 At December 31, 2016, our holdings of obligations of states and political subdivisions included general obligation bonds with an aggregate fair value of $220.1 million and an amortized cost of $211.0 million. Our holdings at December 31, 2016 also included special revenue bonds with an aggregate fair value of $96.8 million and an amortized cost of $91.7 million. With respect to both categories of those bonds at December 31, 2016, we held no securities of any issuer that comprised more than 10% of that category. Education bonds and water and sewer utility bonds represented 62% and 23%, respectively, of our total investments in special revenue bonds based on their carrying values at December 31, 2016. Many of the issuers of the special revenue bonds we held at December 31, 2016 have the authority to impose ad valorem taxes. In that respect, many of the special revenue bonds we held are similar to general obligation bonds. We made reclassifications from available for sale to held to maturity of certain fixed maturities at fair value on November 30, 2013. We segregated within accumulated other comprehensive loss the net unrealized losses of $15.1 million arising prior to the November 30, 2013 reclassification date for fixed maturities we reclassified from available for sale to held to maturity. We are amortizing this balance over the remaining life of the related securities as an adjustment to yield in a manner consistent with the accretion of discount on the same fixed maturities. We recorded amortization of $604,812 and $694,613 in other comprehensive income during the six months ended June 30, 2017 and 2016, respectively. At June 30, 2017 and December 31, 2016, net unrealized losses of $10.4 million and $11.0 million, respectively, remained within accumulated other comprehensive loss. We show below the amortized cost and estimated fair value of our fixed maturities at June 30, 2017 by contractual maturity. Expected maturities may differ from contractual maturities because issuers of the securities may have the right to call or prepay obligations with or without call or prepayment penalties. Amortized Estimated (in thousands) Held to maturity Due in one year or less $ 7,719 $ 7,727 Due after one year through five years 51,321 52,370 Due after five years through ten years 135,275 139,408 Due after ten years 107,243 114,440 Mortgage-backed securities 54,749 55,470 Total held to maturity $ 356,307 $ 369,415 Available for sale Due in one year or less $ 74,570 $ 76,005 Due after one year through five years 88,896 90,496 Due after five years through ten years 102,651 104,184 Due after ten years 23,342 24,418 Mortgage-backed securities 217,734 216,206 Total available for sale $ 507,193 $ 511,309 Gross realized gains and losses from investments before applicable income taxes for the three and six months ended June 30, 2017 and 2016 were as follows: Three Six Months Ended 2017 2016 2017 2016 (in thousands) (in thousands) Gross realized gains: Fixed maturities $ 45 $ 675 $ 50 $ 1,840 Equity securities 1,085 56 3,629 56 1,130 731 3,679 1,896 Gross realized losses: Fixed maturities 30 3 30 258 Equity securities 3 13 3 452 33 16 33 710 Net realized gains $ 1,097 $ 715 $ 3,646 $ 1,186 We held fixed maturities and equity securities with unrealized losses representing declines that we considered temporary at June 30, 2017 as follows: Less Than 12 Months More Than 12 Months Fair Value Unrealized Fair Unrealized (in thousands) U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 41,087 $ 934 $ — $ — Obligations of states and political subdivisions 20,102 385 696 14 Corporate securities 48,822 1,195 6,051 534 Mortgage-backed securities 164,760 2,325 1,196 30 Equity securities 6,222 473 370 249 Totals $ 280,993 $ 5,312 $ 8,313 $ 827 We held fixed maturities and equity securities with unrealized losses representing declines that we considered temporary at December 31, 2016 as follows: Less Than 12 Months More Than 12 Months Fair Value Unrealized Fair Unrealized (in thousands) U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 37,730 $ 1,280 $ — $ — Obligations of states and political subdivisions 40,739 802 710 9 Corporate securities 80,181 2,127 4,707 472 Mortgage-backed securities 168,772 2,728 417 3 Equity securities 5,421 132 — — Totals $ 332,843 $ 7,069 $ 5,834 $ 484 We make estimates concerning the valuation of our investments and the recognition of other-than-temporary declines in the value of our investments. For equity securities, we write down the investment to its fair value, and we reflect the amount of the write-down as a realized loss in our results of operations when we consider the decline in value of an individual equity security investment to be other than temporary. We monitor all investments individually for other-than-temporary declines in value. Generally, we assume there has been an other-than-temporary decline in value if an individual equity security has depreciated in value by more than 20% of our original cost and has been in such an unrealized loss position for more than six months. We held eight equity securities that were in an unrealized loss position at June 30, 2017. Based upon our analysis of general market conditions and underlying factors impacting these equity securities, we considered these declines in value to be temporary. With respect to a debt security that is in an unrealized loss position, we first assess if we intend to sell the debt security. If we determine we intend to sell the debt security, we recognize the impairment loss in our results of operations. If we do not intend to sell the debt security, we determine whether it is more likely than not that we will be required to sell the debt security prior to recovery. If we determine it is more likely than not that we will be required to sell the debt security prior to recovery, we recognize the impairment loss in our results of operations. If we determine it is more likely than not that we will not be required to sell the debt security prior to recovery, we then evaluate whether a credit loss has occurred with respect to that security. We determine whether a credit loss has occurred by comparing the amortized cost of the debt security to the present value of the cash flows we expect to collect. If we expect a cash flow shortfall, we consider that a credit loss has occurred. If we determine that a credit loss has occurred, we consider the impairment to be other than temporary. We then recognize the amount of the impairment loss related to the credit loss in our results of operations, and we recognize the remaining portion of the impairment loss in our other comprehensive income, net of applicable taxes. In addition, we may write down securities in an unrealized loss position based on a number of other factors, including when the fair value of an investment is significantly below its cost, when the financial condition of the issuer of a security has deteriorated, the occurrence of industry, issuer or geographic events that have negatively impacted the value of a security and rating agency downgrades. We held 207 debt securities that were in an unrealized loss position at June 30, 2017. Based upon our analysis of general market conditions and underlying factors impacting these debt securities, we considered these declines in value to be temporary. We amortize premiums and discounts on debt securities over the life of the security as an adjustment to yield using the effective interest method. We compute realized investment gains and losses using the specific identification method. We amortize premiums and discounts on mortgage-backed debt securities using anticipated prepayments. Our investment in affiliate represents our 48.2% ownership interest in DFSC. We account for our investment in affiliate using the equity method of accounting. Under this method, we record our investment at cost, with adjustments for our share of DFSC’s earnings and losses as well as changes in the equity of DFSC due to unrealized gains and losses. We include our share of DFSC’s net income in our results of operations. We have compiled the following summary financial information for DFSC at June 30, 2017 and December 31, 2016 and for the three and six months ended June 30, 2017 and 2016, respectively, from the financial statements of DFSC. The financial information of DFSC at June 30, 2017 and 2016 and for the three and six months then ended is unaudited. Balance sheets: June 30, December 31, (in thousands) Total assets $ 544,943 $ 535,590 Total liabilities $ 464,454 $ 457,101 Stockholders’ equity 80,489 78,489 Total liabilities and stockholders’ equity $ 544,943 $ 535,590 Three Six Income statements: 2017 2016 2017 2016 (in thousands) (in thousands) Net income $ 802 $ 634 $ 1,285 $ 707

Segment Information

Segment Information	6 Months Ended
	Jun. 30, 2017
Segment Reporting [Abstract]
Segment Information	6 - Segment Information We evaluate the performance of our personal lines and commercial lines segments based upon the underwriting results of our insurance subsidiaries using statutory accounting principles (“SAP”) that various state insurance departments prescribe or permit. Our management uses SAP to measure the performance of our insurance subsidiaries instead of United States generally accepted accounting principles (“GAAP”). Financial data by segment for the three and six months ended June 30, 2017 and 2016 is as follows: Three Months Ended 2017 2016 (in thousands) Revenues: Premiums earned Commercial lines $ 79,094 $ 72,962 Personal lines 95,921 88,981 GAAP premiums earned 175,015 161,943 Net investment income 5,650 5,344 Realized investment gains 1,097 715 Equity in earnings of DFSC 387 305 Other 1,432 1,540 Total revenues $ 183,581 $ 169,847 (Loss) income before income taxes: Underwriting (loss) income: Commercial lines $ 3,340 $ 5,577 Personal lines (17,407 ) (3,767 ) SAP underwriting (loss) income (14,067 ) 1,810 GAAP adjustments 2,904 3,051 GAAP underwriting (loss) income (11,163 ) 4,861 Net investment income 5,650 5,344 Realized investment gains 1,097 715 Equity in earnings of DFSC 387 305 Other 633 821 (Loss) income before income taxes $ (3,396 ) $ 12,046 Six Months Ended 2017 2016 (in thousands) Revenues: Premiums earned Commercial lines $ 155,713 $ 142,834 Personal lines 188,458 177,584 GAAP premiums earned 344,171 320,418 Net investment income 11,405 10,890 Realized investment gains 3,646 1,186 Equity in earnings of DFSC 620 341 Other 2,710 3,081 Total revenues $ 362,552 $ 335,916 Income before income taxes: Underwriting (loss) income: Commercial lines $ 3,672 $ 10,417 Personal lines (22,897 ) (1,092 ) SAP underwriting (loss) income (19,225 ) 9,325 GAAP adjustments 5,779 5,007 GAAP underwriting (loss) income (13,446 ) 14,332 Net investment income 11,405 10,890 Realized investment gains 3,646 1,186 Equity in earnings of DFSC 620 341 Other 1,103 1,315 Income before income taxes $ 3,328 $ 28,064

Borrowings

Borrowings	6 Months Ended
	Jun. 30, 2017
Debt Disclosure [Abstract]
Borrowings	7 - Borrowings Lines of Credit In July 2017, we renewed our existing credit agreement with Manufacturers and Traders Trust Company (“M&T”) relating to a $60.0 million unsecured, revolving line of credit. The line of credit expires in July 2020. We have the right to request a one-year extension of the credit agreement as of each anniversary date of the credit agreement. At June 30, 2017, we had $34.0 million in outstanding borrowings from M&T and had the ability to borrow an additional $26.0 million at interest rates equal to M&T’s current prime rate or the then current LIBOR rate plus 2.25%. The interest rate on our outstanding borrowings from M&T is adjustable quarterly, and, at June 30, 2017, that interest rate was 3.48%. We pay a fee of 0.2% per annum on the loan commitment amount regardless of usage. The credit agreement requires our compliance with certain covenants. These covenants include minimum levels of our net worth, leverage ratio, statutory surplus and the A.M. Best ratings of our insurance subsidiaries. We were in compliance with all requirements of the credit agreement during the six months ended June 30, 2017. MICO is a member of the Federal Home Loan Bank (“FHLB”) of Indianapolis. Through its membership, MICO has the ability to issue debt to the FHLB of Indianapolis in exchange for cash advances. MICO had no outstanding borrowings with the FHLB of Indianapolis at June 30, 2017. The table below presents the amount of FHLB of Indianapolis stock MICO purchased, collateral pledged and assets related to MICO’s membership in the FHLB of Indianapolis at June 30, 2017. FHLB of Indianapolis stock purchased and owned $ 267,700 Collateral pledged, at par (carrying value $2,750,395) 2,850,000 Borrowing capacity currently available 2,620,278 Atlantic States is a member of the FHLB of Pittsburgh. Through its membership, Atlantic States has the ability to issue debt to the FHLB of Pittsburgh in exchange for cash advances. Atlantic States had $35.0 million in outstanding advances at June 30, 2017. The interest rate on the advances was 1.25% at June 30, 2017. The table below presents the amount of FHLB of Pittsburgh stock Atlantic States purchased, collateral pledged and assets related to Atlantic States’ membership in the FHLB of Pittsburgh at June 30, 2017. FHLB of Pittsburgh stock purchased and owned $ 1,599,700 Collateral pledged, at par (carrying value $36,267,678) 36,657,236 Borrowing capacity currently available 200,313 Subordinated Debentures Donegal Mutual holds a $5.0 million surplus note that MICO issued to increase MICO’s statutory surplus. The surplus note carries an interest rate of 5.00%, and any repayment of principal or payment of interest on the surplus note requires prior approval of the Michigan Department of Insurance and Financial Services.

Share-Based Compensation

Share-Based Compensation	6 Months Ended
	Jun. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	8 - Share–Based Compensation We measure all share-based payments to employees, including grants of stock options, and use a fair-value-based method for the recording of related compensation expense in our consolidated statements of income. In determining the expense we record for stock options granted to directors and employees of our subsidiaries and affiliates, we estimate the fair value of each option award on the date of grant using the Black-Scholes option pricing model. The significant assumptions we utilize in applying the Black-Scholes option pricing model are the risk-free interest rate, the expected term, the dividend yield and the expected volatility. We charged compensation expense related to our stock compensation plans against income before income taxes of $602,380 and $807,252 for the three months ended June 30, 2017 and 2016, respectively, with a corresponding income tax benefit of $210,833 and $282,538, respectively. We charged compensation expense related to our stock compensation plans against income before income taxes of $1.2 million and $1.6 million for the six months ended June 30, 2017 and 2016, respectively, with a corresponding income tax benefit of $420,068 and $565,441, respectively. At June 30, 2017, we had $2.5 million of unrecognized compensation expense related to nonvested share-based compensation granted under our stock compensation plans that we expect to recognize over a weighted average period of approximately 1.7 years. We received cash from option exercises under all stock compensation plans during the three months ended June 30, 2017 and 2016 of $652,027 and $3.4 million, respectively. We received cash from option exercises under all stock compensation plans during the six months ended June 30, 2017 and 2016 of $2.2 million and $4.1 million, respectively.We realized actual tax benefits for the tax deductions related to option exercises of $70,822 and $243,600 for the three months ended June 30, 2017 and 2016, respectively. We realized actual tax benefits for the tax deductions related to option exercises of $178,356 and $278,196 for the six months ended June 30, 2017 and 2016, respectively.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	9 - Fair Value Measurements We account for financial assets using a framework that establishes a hierarchy that ranks the quality and reliability of the inputs, or assumptions, we use in the determination of fair value, and we classify financial assets and liabilities carried at fair value in one of the following three categories: Level 1 - quoted prices in active markets for identical assets and liabilities; Level 2 - directly or indirectly observable inputs other than Level 1 quoted prices; and Level 3 - unobservable inputs not corroborated by market data. For investments that have quoted market prices in active markets, we use the quoted market price as fair value and include these investments in Level 1 of the fair value hierarchy. We classify publicly-traded equity securities as Level 1. When quoted market prices in active markets are not available, we base fair values on quoted market prices of comparable instruments or price estimates we obtain from independent pricing services and include these investments in Level 2 of the fair value hierarchy. We classify our fixed maturity investments as Level 2. Our fixed maturity investments consist of U.S. Treasury securities and obligations of U.S. government corporations and agencies, obligations of states and political subdivisions, corporate securities and mortgage-backed securities. We present our investments in available-for-sale fixed maturity and equity securities at estimated fair value. The estimated fair value of a security may differ from the amount that could be realized if we sold the security in a forced transaction. In addition, the valuation of fixed maturity investments is more subjective when markets are less liquid, increasing the potential that the estimated fair value does not reflect the price at which an actual transaction would occur. We utilize nationally recognized independent pricing services to estimate fair values or obtain market quotations for substantially all of our fixed maturity and equity investments. These pricing services utilize market quotations for fixed maturity and equity securities that have quoted prices in active markets. For fixed maturity securities that generally do not trade on a daily basis, the pricing services prepare estimates of fair value measurements based predominantly on observable market inputs. The pricing services do not use broker quotes in determining the fair values of our investments. Our investment personnel review the estimates of fair value the pricing services provide to determine if the estimates we obtain from the pricing services are representative of fair values based upon our investment personnel’s general knowledge of the market, their research findings related to unusual fluctuations in value and their comparison of such values to execution prices for similar securities. Our investment personnel regularly monitor the market, current trading ranges for similar securities and the pricing of specific investments. Our investment personnel review all pricing estimates that we receive from the pricing services against their expectations with respect to pricing based on fair market curves, security ratings, coupon rates, security types and recent trading activity. Our investment personnel review documentation with respect to the pricing services’ pricing methodology that they obtain periodically to determine if the primary pricing sources, market inputs and pricing frequency for various security types are reasonable. At June 30, 2017, we received two estimates per security from the pricing services, and we priced substantially all of our Level 1 and Level 2 investments using those prices. In our review of the estimates the pricing services provided at June 30, 2017, we did not identify any material discrepancies, and we did not make any adjustments to the estimates the pricing services provided. We present our cash and short-term investments at estimated fair value. We classify these items as Level 1. The carrying values we report in our balance sheet for premium receivables and reinsurance receivables and payables for premiums and paid losses and loss expenses approximate their fair values. The carrying amounts we report in our balance sheet for our subordinated debentures and borrowings under lines of credit approximate their fair values. We classify these items as Level 3. We evaluate our assets and liabilities on a recurring basis to determine the appropriate level at which to classify them for each reporting period. The following table presents our fair value measurements for our investments in available-for-sale fixed maturity and equity securities at June 30, 2017: Fair Value Measurements Using Fair Value Quoted Prices in Significant Significant (in thousands) U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 38,834 $ — $ 38,834 $ — Obligations of states and political subdivisions 162,426 — 162,426 — Corporate securities 93,843 — 93,843 — Mortgage-backed securities 216,206 — 216,206 — Equity securities 33,871 33,871 — — Total investments in the fair value hierarchy 545,180 33,871 511,309 — Investment measured at net asset value 12,445 — — — Totals $ 557,625 $ 33,871 $ 511,309 $ — We did not transfer any investments between Levels 1 and 2 during the six months ended June 30, 2017. The following table presents our fair value measurements for our investments in available-for-sale fixed maturity and equity securities at December 31, 2016: Fair Value Measurements Using Fair Value Quoted Prices in Significant Significant (in thousands) U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 38,588 $ — $ 38,588 $ — Obligations of states and political subdivisions 186,083 — 186,083 — Corporate securities 87,456 — 87,456 — Mortgage-backed securities 202,948 — 202,948 — Equity securities 35,922 35,922 — — Total investments in the fair value hierarchy 550,997 35,922 515,075 — Investment measured at net asset value 11,166 — — — Totals $ 562,163 $ 35,922 $ 515,075 $ —

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	10 - Income Taxes At June 30, 2017 and December 31, 2016, respectively, we had no material unrecognized tax benefits or accrued interest and penalties. Tax years 2013 through 2016 remained open for examination at June 30, 2017. We provide a valuation allowance when we believe it is more likely than not that we will not realize some portion of our tax assets. We established a valuation allowance of $440,778 related to a portion of the net operating loss carryforward of Le Mars at January 1, 2004. We have determined that we are not required to establish a valuation allowance for our other deferred tax assets of $45.6 million and $43.1 million at June 30, 2017 and December 31, 2016, respectively, because it is more likely than not that we will realize these deferred tax assets through reversals of existing temporary differences, future taxable income and the implementation of tax planning strategies. Our deferred tax assets include a net operating loss carryforward of $2.0 million related to Le Mars, which will begin to expire in 2020 if not previously utilized. This carryforward is subject to an annual limitation in the amount that we can use in any one year of approximately $376,000. Our deferred tax assets also include an alternative minimum tax credit carryforward of $7.7 million with an indefinite life.

Liability for Losses and Loss E

Liability for Losses and Loss Expenses	6 Months Ended
	Jun. 30, 2017
Text Block [Abstract]
Liability for Losses and Loss Expenses	11 - Liability for Losses and Loss Expenses The establishment of an appropriate liability for losses and loss expenses is an inherently uncertain process, and we can provide no assurance that our insurance subsidiaries’ ultimate liability will not exceed their loss and loss expense reserves and have an adverse effect on our results of operations and financial condition. Furthermore, we cannot predict the timing, frequency and extent of adjustments to our insurance subsidiaries’ estimated future liabilities, because the historical conditions and events that serve as a basis for our insurance subsidiaries’ estimates of ultimate claim costs may change. As is the case for substantially all property and casualty insurance companies, our insurance subsidiaries have found it necessary in the past to increase their estimated future liabilities for losses and loss expenses in certain periods, and, in other periods, their estimated future liabilities for losses and loss expenses have exceeded their actual liabilities. Changes in our insurance subsidiaries’ estimate of their liability for losses and loss expenses generally reflect actual payments and their evaluation of information received subsequent to the prior reporting date. We summarize activity in our insurance subsidiaries’ liability for losses and loss expenses as follows: Six Months Ended June 30, 2017 2016 (in thousands) Balance at January 1 $ 606,665 $ 578,205 Less reinsurance recoverable (259,147 ) (256,151 ) Net balance at January 1 347,518 322,054 Incurred related to: Current year 234,045 195,036 Prior years 8,394 3,736 Total incurred 242,439 198,772 Paid related to: Current year 120,392 98,170 Prior years 99,224 96,392 Total paid 219,616 194,562 Net balance at end of period 370,341 326,264 Plus reinsurance recoverable 272,905 250,901 Balance at end of period $ 643,246 $ 577,165 Our insurance subsidiaries recognized an increase in their liability for losses and loss expenses of prior years of $8.4 million and $3.7 million for the six months ended June 30, 2017 and 2016, respectively. Our insurance subsidiaries made no significant changes in their reserving philosophy, key reserving assumptions or claims management personnel, and our insurance subsidiaries have made no significant offsetting changes in estimates that increased or decreased their loss and loss expense reserves in those periods. The 2017 development represented 2.4% of the December 31, 2016 net carried reserves and resulted primarily from higher-than-expected severity in the commercial multi-peril and commercial automobile liability lines of business, offset by lower-than-expected severity in the workers’ compensation line of business, in accident years prior to 2017. The majority of the 2017 development related to increases in the liability for losses and loss expenses of prior years for Atlantic States and Peninsula. The 2016 development represented 1.2% of the December 31, 2015 net carried reserves and resulted primarily from higher-than-expected severity in the commercial multi-peril and commercial automobile liability lines of business, offset by lower-than-expected severity in the workers’ compensation line of business, in accident years prior to 2016. The majority of the 2016 development related to increases in the liability for losses and loss expenses of prior years for Atlantic States and Peninsula. Short-duration contracts are contracts for which our insurance subsidiaries receive premiums that they recognize as revenue over the period of the contract in proportion to the amount of insurance protection our insurance subsidiaries provide. Our insurance subsidiaries consider the policies they issue to be short-duration contracts. We consider our insurance subsidiaries’ material lines of business to be personal automobile, homeowners, commercial automobile, commercial multi-peril and workers’ compensation. Our insurance subsidiaries determine incurred but not reported (“IBNR”) reserves by subtracting the cumulative loss and loss expense amounts our insurance subsidiaries have paid and the case reserves our insurance subsidiaries have established at the balance sheet date from their actuaries’ estimate of the ultimate cost of losses and loss expenses. Accordingly, our insurance subsidiaries’ IBNR reserves include their actuaries’ projections of the cost of unreported claims as well as their actuaries’ projected development of case reserves on known claims and reopened claims. Our insurance subsidiaries’ methodology for estimating IBNR reserves has been in place for many years, and their actuaries made no significant changes to that methodology during the six months ended June 30, 2017. The actuaries for our insurance subsidiaries generally prepare an initial estimate for ultimate losses and loss expenses for the current accident year by multiplying earned premium by an expected loss ratio for each line of business our insurance subsidiaries write. Expected loss ratios represent the actuaries’ expectation of losses at the time our insurance subsidiaries price and write their policies and before the emergence of any actual claims experience. The actuaries determine an expected loss ratio by analyzing historical experience and adjusting for loss cost trends, loss frequency and severity trends, premium rate level changes, reported and paid loss emergence patterns and other known or observed factors. The actuaries use a variety of actuarial methods to estimate the ultimate cost of losses and loss expenses. These methods include paid loss development, incurred loss development and the Bornhuetter-Ferguson method. The actuaries base their selection of a point estimate on a judgmental weighting of the estimates each of these methods produce. The actuaries consider loss frequency and severity trends when they develop expected loss ratios and point estimates. Loss frequency is a measure of the number of claims per unit of insured exposure, and loss severity is a measure of the average size of claims. Factors that affect loss frequency include changes in weather patterns and economic activity. Factors that affect loss severity include changes in policy limits, reinsurance retentions, inflation rates and judicial interpretations. Our insurance subsidiaries create a claim file when they receive notice of an actual demand for payment, an event that may lead to a demand for payment or when they otherwise determine that a demand for payment could potentially lead to a future demand for payment on another coverage under the same policy or another policy they have issued. In recent years, our insurance subsidiaries have noted an increase in the period of time between the occurrence of a casualty loss event and the date on which they receive notice of a liability claim. Changes in the length of time between the loss occurrence date and the claim reporting date affect the actuaries’ ability to accurately predict loss frequency and the amount of IBNR reserves our insurance subsidiaries require. Our insurance subsidiaries generally create a claim file for a policy at the claimant level by type of coverage and generally recognize one count for each claim event. In certain lines of business where it is common for multiple parties to claim damages arising from a single claim event, our insurance subsidiaries recognize one count for each claimant involved in the event. Atlantic States recognizes one count for each claim event, or claimant involved in a multiple-party claim event, related to losses Atlantic States assumes through its participation in its pooling agreement with Donegal Mutual. Our insurance subsidiaries accumulate the claim counts and report them by line of business.

Impact of New Accounting Standa

Impact of New Accounting Standards	6 Months Ended
	Jun. 30, 2017
Accounting Changes and Error Corrections [Abstract]
Impact of New Accounting Standards	12 - Impact of New Accounting Standards In May 2014, the Financial Accounting Standards Board (the “FASB”) issued guidance that requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. While the guidance will replace most existing GAAP revenue recognition guidance, the scope of the guidance excludes insurance contracts. The new standard is effective on January 1, 2018. The standard permits the use of either the retrospective or the cumulative effect transition method. We do not expect the adoption of this new guidance to have a significant impact on our financial position, results of operations or cash flows. In January 2016, the FASB issued guidance that generally requires entities to measure equity investments at fair value and recognize changes in fair value in their results of operations. The guidance also simplifies the impairment assessment of equity investments without readily determinable fair values by requiring entities to perform a qualitative assessment to identify impairment. The FASB issued other disclosure and presentation improvements related to financial instruments within the guidance. The guidance is effective for annual and interim reporting periods beginning after December 15, 2017. As a result of this guidance, we will reflect changes in the fair value of our equity investments in our results of operations beginning January 1, 2018. In February 2016, the FASB issued guidance that requires lessees to recognize leases, including operating leases, on the lessee’s balance sheet, unless a lease is considered a short-term lease. The guidance also requires entities to make new judgments to identify leases. The guidance is effective for annual and interim reporting periods beginning after December 15, 2018 and permits early adoption. We do not expect the adoption of this new guidance to have a significant impact on our financial position, results of operations or cash flows. In March 2016, the FASB issued guidance that simplifies and improves several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities and classification on the statement of cash flows. The guidance is effective for annual and interim reporting periods beginning after December 15, 2016. The adoption of this guidance did not have a significant impact on our financial position, results of operations or cash flows. In June 2016, the FASB issued guidance that amends previous guidance on the impairment of financial instruments by adding an impairment model that requires an entity to recognize expected credit losses as an allowance rather than impairments as credit losses are incurred. The intent of the guidance is to reduce complexity and result in a more timely recognition of expected credit losses. The guidance is effective for annual and interim reporting periods beginning after December 15, 2019. We do not expect the adoption of this guidance to have a significant impact on our financial position, results of operations or cash flows. In March 2017, the FASB issued guidance that amends previous guidance on the amortization period for certain purchased callable debt securities held at a premium. The new guidance shortens the amortization period to the earliest call date. The intent of the new guidance is to align interest income recognition with the expectations incorporated in the market pricing on the underlying securities. The new standard is effective for annual and interim reporting periods beginning after December 15, 2018, with early adoption permitted. The adoption of this new guidance did not have a significant impact on our financial position, results of operations or cash flows.

Impact of New Accounting Stan22

Impact of New Accounting Standards (Policies)	6 Months Ended
	Jun. 30, 2017
Accounting Changes and Error Corrections [Abstract]
Impact of New Accounting Standards	In May 2014, the Financial Accounting Standards Board (the “FASB”) issued guidance that requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. While the guidance will replace most existing GAAP revenue recognition guidance, the scope of the guidance excludes insurance contracts. The new standard is effective on January 1, 2018. The standard permits the use of either the retrospective or the cumulative effect transition method. We do not expect the adoption of this new guidance to have a significant impact on our financial position, results of operations or cash flows. In January 2016, the FASB issued guidance that generally requires entities to measure equity investments at fair value and recognize changes in fair value in their results of operations. The guidance also simplifies the impairment assessment of equity investments without readily determinable fair values by requiring entities to perform a qualitative assessment to identify impairment. The FASB issued other disclosure and presentation improvements related to financial instruments within the guidance. The guidance is effective for annual and interim reporting periods beginning after December 15, 2017. As a result of this guidance, we will reflect changes in the fair value of our equity investments in our results of operations beginning January 1, 2018. In February 2016, the FASB issued guidance that requires lessees to recognize leases, including operating leases, on the lessee’s balance sheet, unless a lease is considered a short-term lease. The guidance also requires entities to make new judgments to identify leases. The guidance is effective for annual and interim reporting periods beginning after December 15, 2018 and permits early adoption. We do not expect the adoption of this new guidance to have a significant impact on our financial position, results of operations or cash flows. In March 2016, the FASB issued guidance that simplifies and improves several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities and classification on the statement of cash flows. The guidance is effective for annual and interim reporting periods beginning after December 15, 2016. The adoption of this guidance did not have a significant impact on our financial position, results of operations or cash flows. In June 2016, the FASB issued guidance that amends previous guidance on the impairment of financial instruments by adding an impairment model that requires an entity to recognize expected credit losses as an allowance rather than impairments as credit losses are incurred. The intent of the guidance is to reduce complexity and result in a more timely recognition of expected credit losses. The guidance is effective for annual and interim reporting periods beginning after December 15, 2019. We do not expect the adoption of this guidance to have a significant impact on our financial position, results of operations or cash flows. In March 2017, the FASB issued guidance that amends previous guidance on the amortization period for certain purchased callable debt securities held at a premium. The new guidance shortens the amortization period to the earliest call date. The intent of the new guidance is to align interest income recognition with the expectations incorporated in the market pricing on the underlying securities. The new standard is effective for annual and interim reporting periods beginning after December 15, 2018, with early adoption permitted. The adoption of this new guidance did not have a significant impact on our financial position, results of operations or cash flows.

Earnings Per Share (Tables)

Earnings Per Share (Tables)	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Summary of Reconciliation of Numerators and Denominators Used in Basic and Diluted Per Share Computations	The table below presents for the periods indicated a reconciliation of the numerators and denominators we used to compute basic and diluted net (loss) income per share for each class of our common stock: Three Months Ended June 30, 2017 2016 Class A Class B Class A Class B (in thousands, except per share data) Basic net (loss) income per share: Numerator: Allocation of net (loss) income $ (1,858 ) $ (461 ) $ 6,919 $ 1,666 Denominator: Weighted-average shares outstanding 21,705 5,577 20,746 5,577 Basic net (loss) income per share $ (0.09 ) $ (0.08 ) $ 0.33 $ 0.30 Diluted net (loss) income per share: Numerator: Allocation of net (loss) income $ (1,858 ) $ (461 ) $ 6,919 $ 1,666 Denominator: Number of shares used in basic computation 21,705 5,577 20,746 5,577 Weighted-average shares effect of dilutive securities Add: Director and employee stock options 792 — 576 — Number of shares used in diluted computation 22,497 5,577 21,322 5,577 Diluted net (loss) income per share $ (0.08 ) $ (0.08 ) $ 0.32 $ 0.30 Six Months Ended June 30, 2017 2016 Class A Class B Class A Class B (in thousands, except per share data) Basic net income per share: Numerator: Allocation of net income $ 2,282 $ 504 $ 16,412 $ 4,022 Denominator: Weighted-average shares outstanding 21,625 5,577 20,645 5,577 Basic net income per share $ 0.11 $ 0.09 $ 0.79 $ 0.72 Diluted net income per share: Numerator: Allocation of net income $ 2,282 $ 504 $ 16,412 $ 4,022 Denominator: Number of shares used in basic computation 21,625 5,577 20,645 5,577 Weighted-average shares effect of dilutive securities Add: Director and employee stock options 937 — 424 — Number of shares used in diluted computation 22,562 5,577 21,069 5,577 Diluted net income per share $ 0.10 $ 0.09 $ 0.78 $ 0.72
Reconciliation of Diluted Shares Outstanding	We did not include outstanding options to purchase the following number of shares of Class A common stock in our computation of diluted earnings per share because the exercise price of the options exceeded the average market price of our Class A common stock during the applicable periods: Three Months Ended Six Months Ended 2017 2016 2017 2016 Number of options to purchase Class A shares excluded 1,388,400 — 1,388,400 —

Investments (Tables)

Investments (Tables)	6 Months Ended
	Jun. 30, 2017
Investments, Debt and Equity Securities [Abstract]
Summary of Amortized Cost and Estimated Fair Values of Fixed Maturities and Equity Securities	The amortized cost and estimated fair values of our fixed maturities and equity securities at June 30, 2017 were as follows: Amortized Gross Gross Estimated (in thousands) Held to Maturity U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 65,104 $ 1,454 $ 497 $ 66,061 Obligations of states and political subdivisions 133,149 10,574 195 143,528 Corporate securities 103,305 2,338 1,287 104,356 Mortgage-backed securities 54,749 804 83 55,470 Totals $ 356,307 $ 15,170 $ 2,062 $ 369,415 Amortized Gross Gross Estimated (in thousands) Available for Sale U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 39,186 $ 85 $ 437 $ 38,834 Obligations of states and political subdivisions 157,048 5,582 204 162,426 Corporate securities 93,225 1,060 442 93,843 Mortgage-backed securities 217,734 744 2,272 216,206 Fixed maturities 507,193 7,471 3,355 511,309 Equity securities 42,163 4,875 722 46,316 Totals $ 549,356 $ 12,346 $ 4,077 $ 557,625 The amortized cost and estimated fair values of our fixed maturities and equity securities at December 31, 2016 were as follows: Amortized Gross Gross Estimated (in thousands) Held to Maturity U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 61,382 $ 1,255 $ 674 $ 61,963 Obligations of states and political subdivisions 122,793 8,404 369 130,828 Corporate securities 91,555 1,172 1,678 91,049 Mortgage-backed securities 60,371 546 110 60,807 Totals $ 336,101 $ 11,377 $ 2,831 $ 344,647 Amortized Gross Gross Estimated (in thousands) Available for Sale U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 39,094 $ 100 $ 606 $ 38,588 Obligations of states and political subdivisions 179,889 6,637 443 186,083 Corporate securities 87,715 662 921 87,456 Mortgage-backed securities 204,931 637 2,620 202,948 Fixed maturities 511,629 8,036 4,590 515,075 Equity securities 42,432 4,788 132 47,088 Totals $ 554,061 $ 12,824 $ 4,722 $ 562,163
Summary of Amortized Cost and Estimated Fair Value of Fixed Maturities by Contractual Maturity	We show below the amortized cost and estimated fair value of our fixed maturities at June 30, 2017 by contractual maturity. Expected maturities may differ from contractual maturities because issuers of the securities may have the right to call or prepay obligations with or without call or prepayment penalties. Amortized Estimated (in thousands) Held to maturity Due in one year or less $ 7,719 $ 7,727 Due after one year through five years 51,321 52,370 Due after five years through ten years 135,275 139,408 Due after ten years 107,243 114,440 Mortgage-backed securities 54,749 55,470 Total held to maturity $ 356,307 $ 369,415 Available for sale Due in one year or less $ 74,570 $ 76,005 Due after one year through five years 88,896 90,496 Due after five years through ten years 102,651 104,184 Due after ten years 23,342 24,418 Mortgage-backed securities 217,734 216,206 Total available for sale $ 507,193 $ 511,309
Summary of Gross Realized Gains and Losses from Investments before Applicable Income Taxes	Gross realized gains and losses from investments before applicable income taxes for the three and six months ended June 30, 2017 and 2016 were as follows: Three Months Ended Six Months Ended 2017 2016 2017 2016 (in thousands) (in thousands) Gross realized gains: Fixed maturities $ 45 $ 675 $ 50 $ 1,840 Equity securities 1,085 56 3,629 56 1,130 731 3,679 1,896 Gross realized losses: Fixed maturities 30 3 30 258 Equity securities 3 13 3 452 33 16 33 710 Net realized gains $ 1,097 $ 715 $ 3,646 $ 1,186
Summary of Fixed Maturities and Equity Securities with Unrealized Losses	We held fixed maturities and equity securities with unrealized losses representing declines that we considered temporary at June 30, 2017 as follows: Less Than 12 Months More Than 12 Months Fair Value Unrealized Fair Unrealized (in thousands) U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 41,087 $ 934 $ — $ — Obligations of states and political subdivisions 20,102 385 696 14 Corporate securities 48,822 1,195 6,051 534 Mortgage-backed securities 164,760 2,325 1,196 30 Equity securities 6,222 473 370 249 Totals $ 280,993 $ 5,312 $ 8,313 $ 827 We held fixed maturities and equity securities with unrealized losses representing declines that we considered temporary at December 31, 2016 as follows: Less Than 12 Months More Than 12 Months Fair Value Unrealized Fair Value Unrealized (in thousands) U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 37,730 $ 1,280 $ — $ — Obligations of states and political subdivisions 40,739 802 710 9 Corporate securities 80,181 2,127 4,707 472 Mortgage-backed securities 168,772 2,728 417 3 Equity securities 5,421 132 — — Totals $ 332,843 $ 7,069 $ 5,834 $ 484
Summary of Financial Information	The financial information of DFSC at June 30, 2017 and 2016 and for the three and six months then ended is unaudited. Balance sheets: June 30, December 31, (in thousands) Total assets $ 544,943 $ 535,590 Total liabilities $ 464,454 $ 457,101 Stockholders’ equity 80,489 78,489 Total liabilities and stockholders’ equity $ 544,943 $ 535,590 Three Six Income statements: 2017 2016 2017 2016 (in thousands) (in thousands) Net income $ 802 $ 634 $ 1,285 $ 707

Segment Information (Tables)

Segment Information (Tables)	6 Months Ended
	Jun. 30, 2017
Segment Reporting [Abstract]
Summary of Financial Data by Segment	Financial data by segment for the three and six months ended June 30, 2017 and 2016 is as follows: Three Months Ended 2017 2016 (in thousands) Revenues: Premiums earned Commercial lines $ 79,094 $ 72,962 Personal lines 95,921 88,981 GAAP premiums earned 175,015 161,943 Net investment income 5,650 5,344 Realized investment gains 1,097 715 Equity in earnings of DFSC 387 305 Other 1,432 1,540 Total revenues $ 183,581 $ 169,847 (Loss) income before income taxes: Underwriting (loss) income: Commercial lines $ 3,340 $ 5,577 Personal lines (17,407 ) (3,767 ) SAP underwriting (loss) income (14,067 ) 1,810 GAAP adjustments 2,904 3,051 GAAP underwriting (loss) income (11,163 ) 4,861 Net investment income 5,650 5,344 Realized investment gains 1,097 715 Equity in earnings of DFSC 387 305 Other 633 821 (Loss) income before income taxes $ (3,396 ) $ 12,046 Six Months Ended 2017 2016 (in thousands) Revenues: Premiums earned Commercial lines $ 155,713 $ 142,834 Personal lines 188,458 177,584 GAAP premiums earned 344,171 320,418 Net investment income 11,405 10,890 Realized investment gains 3,646 1,186 Equity in earnings of DFSC 620 341 Other 2,710 3,081 Total revenues $ 362,552 $ 335,916 Income before income taxes: Underwriting (loss) income: Commercial lines $ 3,672 $ 10,417 Personal lines (22,897 ) (1,092 ) SAP underwriting (loss) income (19,225 ) 9,325 GAAP adjustments 5,779 5,007 GAAP underwriting (loss) income (13,446 ) 14,332 Net investment income 11,405 10,890 Realized investment gains 3,646 1,186 Equity in earnings of DFSC 620 341 Other 1,103 1,315 Income before income taxes $ 3,328 $ 28,064

Borrowings (Tables)

Borrowings (Tables)	6 Months Ended
	Jun. 30, 2017
FHLB of Indianapolis [Member]
Amount of FHLB of Indianapolis/Pittsburgh Stock Purchased, Collateral Pledged and Assets Related to MICO's/Atlantic States Agreement	The table below presents the amount of FHLB of Indianapolis stock MICO purchased, collateral pledged and assets related to MICO’s membership in the FHLB of Indianapolis at June 30, 2017. FHLB of Indianapolis stock purchased and owned $ 267,700 Collateral pledged, at par (carrying value $2,750,395) 2,850,000 Borrowing capacity currently available 2,620,278
FHLB of Pittsburgh [Member]
Amount of FHLB of Indianapolis/Pittsburgh Stock Purchased, Collateral Pledged and Assets Related to MICO's/Atlantic States Agreement	The table below presents the amount of FHLB of Pittsburgh stock Atlantic States purchased, collateral pledged and assets related to Atlantic States’ membership in the FHLB of Pittsburgh at June 30, 2017. FHLB of Pittsburgh stock purchased and owned $ 1,599,700 Collateral pledged, at par (carrying value $36,267,678) 36,657,236 Borrowing capacity currently available 200,313

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements for Investments in Available-for-Sale Fixed Maturity and Equity Securities	The following table presents our fair value measurements for our investments in available-for-sale fixed maturity and equity securities at June 30, 2017: Fair Value Measurements Using Fair Value Quoted Prices in Significant Significant (in thousands) U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 38,834 $ — $ 38,834 $ — Obligations of states and political subdivisions 162,426 — 162,426 — Corporate securities 93,843 — 93,843 — Mortgage-backed securities 216,206 — 216,206 — Equity securities 33,871 33,871 — — Total investments in the fair value hierarchy 545,180 33,871 511,309 — Investment measured at net asset value 12,445 — — — Totals $ 557,625 $ 33,871 $ 511,309 $ — The following table presents our fair value measurements for our investments in available-for-sale fixed maturity and equity securities at December 31, 2016: Fair Value Measurements Using Fair Value Quoted Prices in Significant Significant (in thousands) U.S. Treasury securities and obligations of U.S. government corporations and agencies $ 38,588 $ — $ 38,588 $ — Obligations of states and political subdivisions 186,083 — 186,083 — Corporate securities 87,456 — 87,456 — Mortgage-backed securities 202,948 — 202,948 — Equity securities 35,922 35,922 — — Total investments in the fair value hierarchy 550,997 35,922 515,075 — Investment measured at net asset value 11,166 — — — Totals $ 562,163 $ 35,922 $ 515,075 $ —

Liability for Losses and Loss28

Liability for Losses and Loss Expenses (Tables)	6 Months Ended
	Jun. 30, 2017
Text Block [Abstract]
Summary of Insurance Subsidiaries' Liability for Losses and Loss Expenses	We summarize activity in our insurance subsidiaries’ liability for losses and loss expenses as follows: Six Months Ended June 30, 2017 2016 (in thousands) Balance at January 1 $ 606,665 $ 578,205 Less reinsurance recoverable (259,147 ) (256,151 ) Net balance at January 1 347,518 322,054 Incurred related to: Current year 234,045 195,036 Prior years 8,394 3,736 Total incurred 242,439 198,772 Paid related to: Current year 120,392 98,170 Prior years 99,224 96,392 Total paid 219,616 194,562 Net balance at end of period 370,341 326,264 Plus reinsurance recoverable 272,905 250,901 Balance at end of period $ 643,246 $ 577,165

Organization - Additional Infor

Organization - Additional Information (Detail)	6 Months Ended	47 Months Ended
	Jun. 30, 2017Segmentshares	Jun. 30, 2017shares	Jul. 18, 2013shares
Business Acquisition [Line Items]
Operations commenced date	Aug. 26, 1986
Stock ownership percentage owned by third party	51.80%
Number of operating segments | Segment	4
Voting power percentage of outstanding common stock	73.00%
Atlantic States [Member]
Business Acquisition [Line Items]
Percentage of share in results of pooled business subsidiary	80.00%
Donegal Mutual [Member]
Business Acquisition [Line Items]
Percentage of share in results of pooled business owned by third party	20.00%
Donegal Financial Services Corporation [Member]
Business Acquisition [Line Items]
Outstanding stock ownership percentage	48.20%	48.20%
Class A Common Stock [Member]
Business Acquisition [Line Items]
Stock ownership percentage held by major shareholder	45.00%
Class A Common Stock [Member] | Stock Repurchase Program Two [Member]
Business Acquisition [Line Items]
Authority to purchase shares			500,000
Common stock shares purchased	0	57,658
Class B Common Stock [Member]
Business Acquisition [Line Items]
Stock ownership percentage held by major shareholder	83.00%

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2017
Equity [Abstract]
Minimum percentage of class A common stock declared dividend excess over class B dividend	10.00%

Earnings Per Share - Summary of

Earnings Per Share - Summary of Reconciliation of Numerators and Denominators Used in Basic and Diluted Per Share Computations (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Class A Common Stock [Member]
Numerator:
Allocation of net (loss) income	$ (1,858)	$ 6,919	$ 2,282	$ 16,412
Denominator:
Weighted-average shares outstanding	21,705	20,746	21,625	20,645
Basic net (loss) income per share	$ (0.09)	$ 0.33	$ 0.11	$ 0.79
Numerator:
Allocation of net (loss) income	$ (1,858)	$ 6,919	$ 2,282	$ 16,412
Denominator:
Number of shares used in basic computation	21,705	20,746	21,625	20,645
Weighted-average shares effect of dilutive securities
Add: Director and employee stock options	792	576	937	424
Number of shares used in diluted computation	22,497	21,322	22,562	21,069
Diluted net (loss) income per share	$ (0.08)	$ 0.32	$ 0.10	$ 0.78
Class B Common Stock [Member]
Numerator:
Allocation of net (loss) income	$ (461)	$ 1,666	$ 504	$ 4,022
Denominator:
Weighted-average shares outstanding	5,577	5,577	5,577	5,577
Basic net (loss) income per share	$ (0.08)	$ 0.30	$ 0.09	$ 0.72
Numerator:
Allocation of net (loss) income	$ (461)	$ 1,666	$ 504	$ 4,022
Denominator:
Number of shares used in basic computation	5,577	5,577	5,577	5,577
Weighted-average shares effect of dilutive securities
Number of shares used in diluted computation	5,577	5,577	5,577	5,577
Diluted net (loss) income per share	$ (0.08)	$ 0.30	$ 0.09	$ 0.72

Earnings Per Share - Reconcilia

Earnings Per Share - Reconciliation of Diluted Shares Outstanding (Detail) - shares	3 Months Ended	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2017
Earnings Per Share [Abstract]
Number of options to purchase Class A shares excluded	1,388,400	1,388,400

Reinsurance - Additional Inform

Reinsurance - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2017USD ($)
Ceded Credit Risk [Line Items]
Loss reinsurance, set retention amount	$ 1,000,000
Percentage of accumulation of losses	100.00%
Catastrophe reinsurance, set retention amount	$ 5,000,000
Catastrophe reinsurance, deductible amount	$ 1,000,000
Atlantic States [Member]
Ceded Credit Risk [Line Items]
Percentage of share in results of pooled business subsidiary	80.00%
Donegal Mutual [Member]
Ceded Credit Risk [Line Items]
Percentage of share in results of pooled business owned by third party	20.00%
Maximum amount of loss coverage under reinsurance agreement of property catastrophe	$ 170,000,000

Investments - Summary of Amorti

Investments - Summary of Amortized Cost and Estimated Fair Values of Fixed Maturities and Equity Securities (Detail) - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Schedule of Equity Method Investments [Line Items]
Total held to maturity, Amortized Cost	$ 356,306,558	$ 336,100,948
Held to Maturity, Gross Unrealized Gains	15,170,000	11,377,000
Held to Maturity, Gross Unrealized Losses	2,062,000	2,831,000
Total held to maturity, Estimated Fair Value	369,415,000	344,647,000
Available for Sale, Amortized Cost	549,356,000	554,061,000
Available for Sale, Gross Unrealized Gains	12,346,000	12,824,000
Available for Sale, Gross Unrealized Losses	4,077,000	4,722,000
Available for Sale, Estimated Fair Value	557,625,000	562,163,000
U.S. Treasury Securities and Obligations of U.S. Government Corporations and Agencies [Member]
Schedule of Equity Method Investments [Line Items]
Total held to maturity, Amortized Cost	65,104,000	61,382,000
Held to Maturity, Gross Unrealized Gains	1,454,000	1,255,000
Held to Maturity, Gross Unrealized Losses	497,000	674,000
Total held to maturity, Estimated Fair Value	66,061,000	61,963,000
Available for Sale, Amortized Cost	39,186,000	39,094,000
Available for Sale, Gross Unrealized Gains	85,000	100,000
Available for Sale, Gross Unrealized Losses	437,000	606,000
Available for Sale, Estimated Fair Value	38,834,000	38,588,000
Obligations of States and Political Subdivisions [Member]
Schedule of Equity Method Investments [Line Items]
Total held to maturity, Amortized Cost	133,149,000	122,793,000
Held to Maturity, Gross Unrealized Gains	10,574,000	8,404,000
Held to Maturity, Gross Unrealized Losses	195,000	369,000
Total held to maturity, Estimated Fair Value	143,528,000	130,828,000
Available for Sale, Amortized Cost	157,048,000	179,889,000
Available for Sale, Gross Unrealized Gains	5,582,000	6,637,000
Available for Sale, Gross Unrealized Losses	204,000	443,000
Available for Sale, Estimated Fair Value	162,426,000	186,083,000
Corporate Securities [Member]
Schedule of Equity Method Investments [Line Items]
Total held to maturity, Amortized Cost	103,305,000	91,555,000
Held to Maturity, Gross Unrealized Gains	2,338,000	1,172,000
Held to Maturity, Gross Unrealized Losses	1,287,000	1,678,000
Total held to maturity, Estimated Fair Value	104,356,000	91,049,000
Available for Sale, Amortized Cost	93,225,000	87,715,000
Available for Sale, Gross Unrealized Gains	1,060,000	662,000
Available for Sale, Gross Unrealized Losses	442,000	921,000
Available for Sale, Estimated Fair Value	93,843,000	87,456,000
Mortgage-Backed Securities [Member]
Schedule of Equity Method Investments [Line Items]
Total held to maturity, Amortized Cost	54,749,000	60,371,000
Held to Maturity, Gross Unrealized Gains	804,000	546,000
Held to Maturity, Gross Unrealized Losses	83,000	110,000
Total held to maturity, Estimated Fair Value	55,470,000	60,807,000
Available for Sale, Amortized Cost	217,734,000	204,931,000
Available for Sale, Gross Unrealized Gains	744,000	637,000
Available for Sale, Gross Unrealized Losses	2,272,000	2,620,000
Available for Sale, Estimated Fair Value	216,206,000	202,948,000
Equity Securities [Member]
Schedule of Equity Method Investments [Line Items]
Available for Sale, Amortized Cost	42,163,000	42,432,000
Available for Sale, Gross Unrealized Gains	4,875,000	4,788,000
Available for Sale, Gross Unrealized Losses	722,000	132,000
Available for Sale, Estimated Fair Value	46,316,000	47,088,000
Fixed Maturities [Member]
Schedule of Equity Method Investments [Line Items]
Available for Sale, Amortized Cost	507,193,000	511,629,000
Available for Sale, Gross Unrealized Gains	7,471,000	8,036,000
Available for Sale, Gross Unrealized Losses	3,355,000	4,590,000
Available for Sale, Estimated Fair Value	$ 511,309,000	$ 515,075,000

Investments - Additional Inform

Investments - Additional Information (Detail)	Nov. 30, 2013USD ($)	Jun. 30, 2017USD ($)Securities	Jun. 30, 2016USD ($)	Dec. 31, 2016USD ($)
Schedule of Investments [Line Items]
Net unrealized losses arising prior to reclassification date and classified in accumulated other comprehensive loss	$ 15,100,000
Amortization of unrealized losses recorded in other comprehensive income		$ 604,812	$ 694,613
Accumulated other comprehensive loss		$ (1,551,482)		$ (2,254,271)
Depreciation of original cost value		20.00%
Time period for which individual security should be in unrealized position of twenty percentage or more to assume it as other than temporary decline		More than six months
Donegal Financial Services Corporation [Member]
Schedule of Investments [Line Items]
Percentage of ownership interest		48.20%
Equity Securities [Member]
Schedule of Investments [Line Items]
Number of fixed maturity securities classified as available for sale | Securities		8
Obligations of States and Political Subdivisions [Member]
Schedule of Investments [Line Items]
Aggregate fair value of bond held		$ 209,900,000		220,100,000
Amortized cost of bond held		199,700,000		211,000,000
Special Revenue Bonds [Member]
Schedule of Investments [Line Items]
Aggregate fair value of bond held		96,100,000		96,800,000
Amortized cost of bond held		$ 90,500,000		$ 91,700,000
Education Bonds [Member]
Schedule of Investments [Line Items]
Percentage of investments in special revenue bonds		58.00%		62.00%
Water and Sewer Utility Bonds [Member]
Schedule of Investments [Line Items]
Percentage of investments in special revenue bonds		23.00%		23.00%
Fixed Maturities [Member]
Schedule of Investments [Line Items]
Number of fixed maturity securities classified as available for sale | Securities		207
Accumulated Net Unrealized Investment Losses [Member]
Schedule of Investments [Line Items]
Accumulated other comprehensive loss		$ (10,400,000)		$ (11,000,000)
Minimum [Member]
Schedule of Investments [Line Items]
Percentage of which the company held security of any issuer		10.00%		10.00%

Investments - Summary of Amor36

Investments - Summary of Amortized Cost and Estimated Fair Value of Fixed Maturities by Contractual Maturity (Detail) - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Held to maturity
Due in one year or less, Amortized Cost	$ 7,719,000
Due after one year through five years, Amortized Cost	51,321,000
Due after five years through ten years, Amortized Cost	135,275,000
Due after ten years, Amortized Cost	107,243,000
Mortgage-backed securities, Amortized Cost	54,749,000
Total held to maturity, Amortized Cost	356,306,558	$ 336,100,948
Available for sale
Due in one year or less, Amortized Cost	74,570,000
Due after one year through five years, Amortized Cost	88,896,000
Due after five years through ten years, Amortized Cost	102,651,000
Due after ten years, Amortized Cost	23,342,000
Mortgage-backed securities, Amortized Cost	217,734,000
Total available for sale, Amortized Cost	507,193,000
Held to maturity
Due in one year or less, Estimated Fair Value	7,727,000
Due after one year through five years, Estimated Fair Value	52,370,000
Due after five years through ten years, Estimated Fair Value	139,408,000
Due after ten years, Estimated Fair Value	114,440,000
Mortgage-backed securities, Estimated Fair Value	55,470,000
Total held to maturity, Estimated Fair Value	369,415,000	344,647,000
Available for sale
Due in one year or less, Estimated Fair Value	76,005,000
Due after one year through five years, Estimated Fair Value	90,496,000
Due after five years through ten years, Estimated Fair Value	104,184,000
Due after ten years, Estimated Fair Value	24,418,000
Mortgage-backed securities, Estimated Fair Value	216,206,000
Total available for sale, Estimated Fair Value	$ 511,309,135	$ 515,074,940

Investments - Summary of Gross

Investments - Summary of Gross Realized Gains and Losses from Investments before Applicable Income Taxes (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Gain (Loss) on Investments [Line Items]
Gross realized gains	$ 1,130,000	$ 731,000	$ 3,679,000	$ 1,896,000
Gross realized losses	33,000	16,000	33,000	710,000
Net realized gains (losses)	1,097,306	715,177	3,646,281	1,186,118
Fixed Maturities [Member]
Gain (Loss) on Investments [Line Items]
Gross realized gains	45,000	675,000	50,000	1,840,000
Gross realized losses	30,000	3,000	30,000	258,000
Equity Securities [Member]
Gain (Loss) on Investments [Line Items]
Gross realized gains	1,085,000	56,000	3,629,000	56,000
Gross realized losses	$ 3,000	$ 13,000	$ 3,000	$ 452,000

Investments - Summary of Fixed

Investments - Summary of Fixed Maturities and Equity Securities with Unrealized Losses (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	$ 280,993	$ 332,843
Less Than 12 Months, Unrealized Losses	5,312	7,069
More Than 12 Months, Fair Value	8,313	5,834
More Than 12 Months, Unrealized Losses	827	484
U.S. Treasury Securities and Obligations of U.S. Government Corporations and Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	41,087	37,730
Less Than 12 Months, Unrealized Losses	934	1,280
Obligations of States and Political Subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	20,102	40,739
Less Than 12 Months, Unrealized Losses	385	802
More Than 12 Months, Fair Value	696	710
More Than 12 Months, Unrealized Losses	14	9
Corporate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	48,822	80,181
Less Than 12 Months, Unrealized Losses	1,195	2,127
More Than 12 Months, Fair Value	6,051	4,707
More Than 12 Months, Unrealized Losses	534	472
Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	164,760	168,772
Less Than 12 Months, Unrealized Losses	2,325	2,728
More Than 12 Months, Fair Value	1,196	417
More Than 12 Months, Unrealized Losses	30	3
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Fair Value	6,222	5,421
Less Than 12 Months, Unrealized Losses	473	$ 132
More Than 12 Months, Fair Value	370
More Than 12 Months, Unrealized Losses	$ 249

Investments - Summary of Financ

Investments - Summary of Financial Information (Detail) - Donegal Financial Services Corporation [Member] - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Balance sheets:
Total assets	$ 544,943,000		$ 544,943,000		$ 535,590,000
Total liabilities	464,454,000		464,454,000		457,101,000
Stockholders' equity	80,489,000		80,489,000		78,489,000
Total liabilities and stockholders' equity	544,943,000		544,943,000		$ 535,590,000
Income statements:
Net income	$ 802,000	$ 634,000	$ 1,285,000	$ 707,000

Segment Information - Summary o

Segment Information - Summary of Financial Data by Segment (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Premiums earned
Net premiums earned	$ 175,014,872	$ 161,942,637	$ 344,171,019	$ 320,417,916
Net investment income	5,649,870	5,343,883	11,405,269	10,890,392
Realized investment gains	1,097,306	715,177	3,646,281	1,186,118
Equity in earnings of DFSC	386,615	305,475	619,565	340,702
Other	1,432,000	1,540,000	2,710,000	3,081,000
Total revenues	183,580,716	169,846,867	362,551,679	335,915,643
Underwriting (loss) income:
SAP underwriting (loss) income	(14,067,000)	1,810,000	(19,225,000)	9,325,000
GAAP adjustments	2,904,000	3,051,000	5,779,000	5,007,000
GAAP underwriting (loss) income	(11,163,000)	4,861,000	(13,446,000)	14,332,000
Net investment income	5,649,870	5,343,883	11,405,269	10,890,392
Realized investment gains	1,097,306	715,177	3,646,281	1,186,118
Equity in earnings of DFSC	386,615	305,475	619,565	340,702
Other	633,000	821,000	1,103,000	1,315,000
(Loss) income before income tax (benefit) expense	(3,396,469)	12,045,692	3,328,360	28,064,231
Commercial Lines [Member]
Premiums earned
Net premiums earned	79,094,000	72,962,000	155,713,000	142,834,000
Underwriting (loss) income:
SAP underwriting (loss) income	3,340,000	5,577,000	3,672,000	10,417,000
Personal Lines [Member]
Premiums earned
Net premiums earned	95,921,000	88,981,000	188,458,000	177,584,000
Underwriting (loss) income:
SAP underwriting (loss) income	$ (17,407,000)	$ (3,767,000)	$ (22,897,000)	$ (1,092,000)

Borrowings - Additional Informa

Borrowings - Additional Information (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2017	Jul. 31, 2017	Dec. 31, 2016
Line of Credit Facility [Line Items]
Line of credit expiration month and year	2020-07
Outstanding borrowings	$ 69,000,000		$ 69,000,000
Line of credit, interest rate description	Interest rates equal to M&T's current prime rate or the then current LIBOR rate plus 2.25%
Percentage commitment fee	0.20%
Manufacturers and Traders Trust Company [Member]
Line of Credit Facility [Line Items]
Outstanding borrowings	$ 34,000,000
Line of credit facility remaining borrowing capacity	$ 26,000,000
Interest rate on borrowings	3.48%
Line of credit covenant description	The credit agreement requires our compliance with certain covenants. These covenants include minimum levels of our net worth, leverage ratio, statutory surplus and the A.M. Best ratings of our insurance subsidiaries. We were in compliance with all requirements of the credit agreement during the six months ended June 30, 2017.
FHLB of Indianapolis [Member] | MICO [Member]
Line of Credit Facility [Line Items]
Outstanding advances	$ 0
FHLB of Pittsburgh [Member] | Atlantic States [Member]
Line of Credit Facility [Line Items]
Right to request for extension of credit agreement with Manufacturers and Traders Trust Company	200,313
Outstanding advances	$ 35,000,000
Revolving Credit Facility [Member] | Manufacturers and Traders Trust Company [Member] | Subsequent Event [Member]
Line of Credit Facility [Line Items]
Right to request for extension of credit agreement with Manufacturers and Traders Trust Company		$ 60,000,000
Lines of Credit [Member] | London Interbank Offered Rate (LIBOR) [Member]
Line of Credit Facility [Line Items]
Debt instrument basis spread on variable rate	2.25%
Lines of Credit [Member] | FHLB of Pittsburgh [Member] | Atlantic States [Member]
Line of Credit Facility [Line Items]
Interest rate on advances	1.25%
Subordinated Debentures [Member]
Line of Credit Facility [Line Items]
Debt instrument stated interest rate	5.00%
Subordinated Debentures [Member] | West Bend Mutual Insurance Company [Member]
Line of Credit Facility [Line Items]
Surplus note	$ 5,000,000

Borrowings - Amount of FHLB of

Borrowings - Amount of FHLB of Indianapolis/Pittsburgh Stock Purchased, Collateral Pledged and Assets Related to MICO's/Atlantic States Agreement (Detail)	Jun. 30, 2017USD ($)
MICO [Member] | FHLB of Indianapolis [Member]
Amount of FHLB of Indianapolis/Pittsburgh stock purchased, collateral pledged and assets related to MICO's/Atlantic States Agreement
FHLB stock purchased and owned as part of the agreement	$ 267,700
Collateral pledged, at par	2,850,000
Borrowing capacity currently available	2,620,278
Atlantic States [Member] | FHLB of Pittsburgh [Member]
Amount of FHLB of Indianapolis/Pittsburgh stock purchased, collateral pledged and assets related to MICO's/Atlantic States Agreement
FHLB stock purchased and owned as part of the agreement	1,599,700
Collateral pledged, at par	36,657,236
Borrowing capacity currently available	$ 200,313

Borrowings - Amount of FHLB o43

Borrowings - Amount of FHLB of Indianapolis/Pittsburgh Stock Purchased, Collateral Pledged and Assets Related to MICO's/Atlantic States Agreement (Parenthetical) (Detail)	Jun. 30, 2017USD ($)
FHLB of Indianapolis [Member] | MICO [Member]
Line of Credit Facility [Line Items]
Collateral Pledged at carrying value	$ 2,750,395
FHLB of Pittsburgh [Member] | Atlantic States [Member]
Line of Credit Facility [Line Items]
Collateral Pledged at carrying value	$ 36,267,678

Share-Based Compensation - Addi

Share-Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Compensation expense in stock compensation plans	$ 602,380	$ 807,252	$ 1,200,000	$ 1,600,000
Income tax benefit of stock compensation plans	210,833	282,538	420,068	565,441
Unrecognized compensation expense related to nonvested share-based compensation granted under the plan	2,500,000		$ 2,500,000
Weighted average period of unrecognized compensation expense			1 year 8 months 12 days
Cash from option exercises	652,027	3,400,000	$ 2,200,000	4,100,000
Tax benefit for tax deductions related to option exercises	$ 70,822	$ 243,600	$ 178,356	$ 278,196

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Measurements for Investments in Available-for-Sale Fixed Maturity and Equity Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	$ 557,625	$ 562,163
U.S. Treasury Securities and Obligations of U.S. Government Corporations and Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	38,834	38,588
Obligations of States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	162,426	186,083
Corporate Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	93,843	87,456
Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	216,206	202,948
Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	46,316	47,088
Assets and Liabilities on Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	557,625	562,163
Assets and Liabilities on Recurring Basis [Member] | Investments Measured at Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	12,445	11,166
Assets and Liabilities on Recurring Basis [Member] | Total Investments in the Fair Value Hierarchy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	545,180	550,997
Assets and Liabilities on Recurring Basis [Member] | Total Investments in the Fair Value Hierarchy [Member] | U.S. Treasury Securities and Obligations of U.S. Government Corporations and Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	38,834	38,588
Assets and Liabilities on Recurring Basis [Member] | Total Investments in the Fair Value Hierarchy [Member] | Obligations of States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	162,426	186,083
Assets and Liabilities on Recurring Basis [Member] | Total Investments in the Fair Value Hierarchy [Member] | Corporate Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	93,843	87,456
Assets and Liabilities on Recurring Basis [Member] | Total Investments in the Fair Value Hierarchy [Member] | Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	216,206	202,948
Assets and Liabilities on Recurring Basis [Member] | Total Investments in the Fair Value Hierarchy [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	33,871	35,922
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Assets and Liabilities on Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	33,871	35,922
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Assets and Liabilities on Recurring Basis [Member] | Total Investments in the Fair Value Hierarchy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	33,871	35,922
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Assets and Liabilities on Recurring Basis [Member] | Total Investments in the Fair Value Hierarchy [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	33,871	35,922
Significant Other Observable Inputs (Level 2) [Member] | Assets and Liabilities on Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	511,309	515,075
Significant Other Observable Inputs (Level 2) [Member] | Assets and Liabilities on Recurring Basis [Member] | Total Investments in the Fair Value Hierarchy [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	511,309	515,075
Significant Other Observable Inputs (Level 2) [Member] | Assets and Liabilities on Recurring Basis [Member] | Total Investments in the Fair Value Hierarchy [Member] | U.S. Treasury Securities and Obligations of U.S. Government Corporations and Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	38,834	38,588
Significant Other Observable Inputs (Level 2) [Member] | Assets and Liabilities on Recurring Basis [Member] | Total Investments in the Fair Value Hierarchy [Member] | Obligations of States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	162,426	186,083
Significant Other Observable Inputs (Level 2) [Member] | Assets and Liabilities on Recurring Basis [Member] | Total Investments in the Fair Value Hierarchy [Member] | Corporate Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	93,843	87,456
Significant Other Observable Inputs (Level 2) [Member] | Assets and Liabilities on Recurring Basis [Member] | Total Investments in the Fair Value Hierarchy [Member] | Mortgage-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities, Fair Value Disclosure	$ 216,206	$ 202,948

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Operating Loss Carryforwards [Line Items]
Other deferred tax assets, net	$ 45,600,000	$ 43,100,000
Alternative minimum tax credit carryforward	$ 7,700,000
Earliest Tax Year [Member]
Operating Loss Carryforwards [Line Items]
Tax years open for examination	2,013
Latest Tax Year [Member]
Operating Loss Carryforwards [Line Items]
Tax years open for examination	2,016
Le Mars [Member]
Operating Loss Carryforwards [Line Items]
Valuation allowance related to the portion of operating loss carryforwards	$ 440,778
Operating loss carryforwards	$ 2,000,000
Operating loss carryforwards expiration period	2,020
Operating loss carryforwards annual limitations in amount on use	$ 376,000

Liability for Losses and Loss47

Liability for Losses and Loss Expenses - Summary of Insurance Subsidiaries' Liability for Losses and Loss Expenses (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Liability for Claims and Claims Adjustment Expense [Abstract]
Balance at January 1	$ 606,664,590	$ 578,205,000
Less reinsurance recoverable	(259,147,000)	(256,151,000)
Net balance at January 1	347,518,000	322,054,000
Incurred related to:
Current year	234,045,000	195,036,000
Prior years	8,394,000	3,736,000
Total incurred	242,439,000	198,772,000
Paid related to:
Current year	120,392,000	98,170,000
Prior years	99,224,000	96,392,000
Total paid	219,616,000	194,562,000
Net balance at end of period	370,341,000	326,264,000
Plus reinsurance recoverable	272,905,000	250,901,000
Balance at end of period	$ 643,246,130	$ 577,165,000

Liability for Losses and Loss48

Liability for Losses and Loss Expenses - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Insurance [Abstract]
Increase (Decrease) in liability for losses and loss expenses of prior years	$ 8,394	$ 3,736
Percentage of 2010 development	2.40%	1.20%