AAON (AAON) 10-Q 3 Aug 17 2017 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2017	Jul. 28, 2017
Document And Entity Information
Entity Registrant Name	AAON INC
Entity Central Index Key	824,142
Document Type	10-Q
Document Period End Date	Jun. 30, 2017
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		52,603,622
Document Fiscal Period Focus	Q2
Document Fiscal Year Focus	2,017

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 33,552	$ 24,153
Certificates of deposit	5,520	5,512
Investments held to maturity at amortized cost	12,732	14,083
Accounts receivable, net	43,114	43,001
Income tax receivable	809	6,239
Notes receivable	26	25
Inventories, net	63,075	47,352
Prepaid expenses and other	888	616
Total current assets	159,716	140,981
Property, plant and equipment:
Land	2,233	2,233
Buildings	83,401	78,806
Machinery and equipment	168,375	158,216
Furniture and fixtures	13,458	12,783
Total property, plant and equipment	267,467	252,038
Less: Accumulated depreciation	142,839	137,146
Property, plant and equipment, net	124,628	114,892
Note receivable	667	657
Total assets	285,011	256,530
Current liabilities:
Revolving credit facility	0	0
Accounts payable	14,108	7,102
Dividends payable	6,849	0
Accrued liabilities	34,293	31,940
Total current liabilities	55,250	39,042
Deferred revenue	1,542	1,498
Deferred tax liabilities	9,895	9,531
Donations	577	561
Commitments and contingencies
Stockholders' equity:
Preferred stock, $.001 par value, 5,000,000 shares authorized, no shares issued	0	0
Common stock, $.004 par value, 100,000,000 shares authorized, 52,615,921 and 52,651,448 issued and outstanding at June 30, 2017 and December 31, 2016, respectively	210	211
Additional paid-in capital	0	0
Retained earnings	217,537	205,687
Total stockholders' equity	217,747	205,898
Total liabilities and stockholders' equity	$ 285,011	$ 256,530

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2017	Dec. 31, 2016
Stockholders' equity:
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 0.004	$ 0.004
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	52,615,921	52,651,448
Common stock, shares outstanding	52,615,921	52,651,448

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement [Abstract]
Net sales	$ 101,326	$ 102,319	$ 187,404	$ 187,741
Cost of sales	69,648	69,572	130,740	129,263
Gross profit	31,678	32,747	56,664	58,478
Selling, general and administrative expenses	11,971	10,561	22,501	19,474
Loss (gain) on disposal of assets	48	(12)	47	(20)
Income from operations	19,659	22,198	34,116	39,024
Interest income, net	71	67	131	141
Other income, net	34	10	45	127
Income before taxes	19,764	22,275	34,292	39,292
Income tax provision	5,970	7,550	10,281	13,016
Net income	$ 13,794	$ 14,725	$ 24,011	$ 26,276
Earnings per share:
Basic (usd per share)	$ 0.26	$ 0.28	$ 0.46	$ 0.47
Diluted (usd per share)	0.26	0.27	0.45	0.47
Cash dividends declared per common share	$ 0.13	$ 0.11	$ 0.13	$ 0.11
Weighted average shares outstanding:
Basic (in shares)	52,615,366	53,036,009	52,624,782	53,028,224
Diluted (in shares)	53,151,134	53,574,702	53,176,425	53,563,676

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - 6 months ended Jun. 30, 2017 - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Paid-in Capital	Retained Earnings
Balance at Dec. 31, 2016	$ 205,898	$ 211	$ 0	$ 205,687
Balance (in shares) at Dec. 31, 2016		52,651
Net income	24,011
Stock options exercised and restricted stock awards granted	1,573		1,573
Stock options exercised and restricted stock awards granted (in shares)		261
Share-based compensation	3,529		3,529
Stock repurchased and retired	(10,434)	$ (1)	(5,102)	(5,331)
Stock repurchased and retired (in shares)		(296)
Dividends	(6,830)			(6,830)
Balance at Jun. 30, 2017	$ 217,747	$ 210	$ 0	$ 217,537
Balance (in shares) at Jun. 30, 2017		52,616

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Operating Activities
Net income	$ 24,011	$ 26,276
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	7,281	6,346
Amortization of bond premiums	29	151
Provision for losses on accounts receivable, net of adjustments	141	(42)
Provision for excess and obsolete inventories	260	308
Share-based compensation	3,529	2,043
Loss (gain) on disposal of assets	47	(20)
Foreign currency transaction gain	(24)	(48)
Interest income on note receivable	(13)	(14)
Deferred	364	(1,851)
Changes in assets and liabilities:
Accounts receivable	(254)	(8,417)
Income taxes	5,430	4,033
Inventories	(15,983)	(1,934)
Prepaid expenses and other	(272)	(550)
Accounts payable	6,801	1,848
Deferred revenue	118	220
Accrued liabilities and donations	2,295	1,252
Net cash provided by operating activities	33,760	29,601
Investing Activities
Capital expenditures	(16,847)	(15,825)
Proceeds from sale of property, plant and equipment	7	1
Investment in certificates of deposits	(5,280)	(4,112)
Maturities of certificates of deposits	5,272	6,000
Purchases of investments held to maturity	(13,241)	(9,782)
Maturities of investments	14,063	3,801
Proceeds from called investments	500	1,010
Principal payments from note receivable	26	26
Net cash used in investing activities	(15,500)	(18,881)
Financing Activities
Borrowings under revolving credit facility	0	761
Payments under revolving credit facility	0	(761)
Stock options exercised	1,573	1,255
Repurchase of stock	(9,368)	(7,233)
Employee taxes paid by withholding shares	(1,066)	(441)
Net cash used in financing activities	(8,861)	(6,419)
Net increase in cash and cash equivalents	9,399	4,301
Cash and cash equivalents, beginning of period	24,153	7,908
Cash and cash equivalents, end of period	$ 33,552	$ 12,209

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 30, 2017
Basis of Presentation and Significant Accounting Policies [Abstract]
Basis of Presentation	General Basis of Presentation The accompanying unaudited consolidated financial statements of AAON, Inc., a Nevada corporation, and our operating subsidiaries, all of which are wholly-owned, (collectively, the “Company”) have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) for interim financial information and with the rules and regulations of the Securities and Exchange Commission (“SEC”). These financial statements have not been audited by the Company's independent registered public accounting firm, except that the consolidated balance sheet at December 31, 2016 is derived from audited consolidated financial statements. Accordingly, they do not include all of the information and notes required by U.S. GAAP for complete financial statements. The financial statements reflect all adjustments (all of which are of a normal recurring nature) which are, in the opinion of management, necessary for a fair statement of the results for the interim periods presented. Interim results are not necessarily indicative of the results that may be expected for a full year. Certain disclosures have been condensed in or omitted from these consolidated financial statements. The accompanying unaudited financial statements should be read in conjunction with the consolidated financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 . All intercompany balances and transactions have been eliminated in consolidation. We are engaged in the engineering, manufacturing, marketing and sale of air conditioning and heating equipment consisting of standard, semi-custom and custom rooftop units, chillers, packaged outdoor mechanical rooms, air handling units, makeup air units, energy recovery units, condensing units, geothermal/water-source heat pumps and coils. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Because these estimates and assumptions require significant judgment, actual results could differ from those estimates and could have a significant impact on our results of operations, financial position and cash flows. We reevaluate our estimates and assumptions as needed, but at a minimum on a quarterly basis. The most significant estimates include, but are not limited to, the allowance for doubtful accounts, inventory reserves, warranty accrual, worker's compensation accrual, medical insurance accrual, income taxes and share-based compensation. Actual results could differ materially from those estimates. Accounting Policies A comprehensive discussion of our critical accounting policies and management estimates is included in Management’s Discussion and Analysis of Financial Condition and Results of Operations in our Annual Report on Form 10-K for the year ended December 31, 2016 . Recent Accounting Pronouncements Changes to U.S. GAAP are established by the Financial Accounting Standards Board ("FASB") in the form of Accounting Standards Updates ("ASUs") to the FASB's Accounting Standards Codification. We consider the applicability and impact of all ASUs. ASUs not listed below were assessed and determined to be either not applicable or are expected to have minimal impact on our consolidated financial statements and notes thereto. In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers , which 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. The ASU will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. In August 2015, with the issuance of ASU 2015-14, the FASB amended the effective date for us to January 1, 2018. The following ASUs were issued in 2016 along with ASU 2014-09 with the same effective dates and transition requirements: • ASU 2016-08, Principal versus Agent Considerations (Reporting Revenue Gross versus Net) , which provides implementation guidance for Topic 606 on principal versus agent considerations. • ASU 2016-10, Identifying Performance Obligations and Licensing , which provides clarification for two aspects of Topic 606: identifying performance obligations and the licensing implementation guidance. • ASU 2016-12, Revenue from Contracts with Customers , which further amends Topic 606. • ASU 2016-20, Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers , which further amends Topic 606. The Company plans to adopt using the retrospective transition method. The Company has begun assessing the impact of ASU 2015-09 and believes the impact will not be material to the consolidated financial statements. Once we adopt ASU 2014-09, we do not anticipate that our internal control framework will materially change, but rather that existing internal controls will be modified and augmented, as necessary, to consider our new revenue recognition policy effective January 1, 2018. In January 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities , which will address certain aspects of recognition, measurement, presentation and disclosure of financial instruments. The ASU becomes effective in the annual reporting period beginning after December 31, 2017, including interim reporting periods. We do not expect ASU 2016-01 will have a material effect on our consolidated financial statements and notes thereto. In May 2017, the FASB issued ASU 2017-09, Scope of Modification Accounting , which addresses changes to the terms or conditions of a share-based payment award. The ASU becomes effective in the annual reporting period beginning after December 15, 2017, including interim reporting periods. We do not expect ASU 2017-09 will have a material effect on our consolidated financial statements and notes thereto.

Revenue Recognition

Revenue Recognition	6 Months Ended
	Jun. 30, 2017
Revenue Recognition [Abstract]
Revenue Recognition	Revenue Recognition We recognize revenues from sales of products when the title and risk of ownership pass to the customer. Final sales prices are fixed based on purchase orders. Sales allowances and customer incentives are treated as reductions to sales and are provided for based on historical experiences and current estimates. Sales of our products are moderately seasonal with the peak period being July - November of each year. In addition, the Company presents revenues net of sales tax and net of certain payments to our independent manufacturer representatives (“Representatives”). Representatives are national companies that are in the business of providing HVAC units and other related products and services to customers. The end user customer orders a bundled group of products and services from the Representative and expects the Representative to fulfill the order. Only after the specifications are agreed to by the Representative and the customer, and the decision is made to use an AAON HVAC unit, will we receive notice of the order. We establish the amount we must receive for our HVAC unit (“minimum sales price”), but do not control the total order price that is negotiated by the Representative with the end user customer. We are responsible for billings and collections resulting from all sales transactions, including those initiated by our Representatives. The Representatives submit the total order price to us for invoicing and collection. The total order price includes our minimum sales price and an additional amount which may include both the Representatives’ fee and amounts due for additional products and services required by the customer. These additional products and services may include controls purchased from another manufacturer to operate the unit, start-up services, and curbs for supporting the unit (“Third Party Products”). All are associated with the purchase of a HVAC unit but may be provided by the Representative or another third party. The Company is under no obligation related to Third Party Products. The Representatives’ fee and Third Party Products amounts (“Due to Representatives”) are paid only after all amounts associated with the order are collected from the customer. The amount of payments to our Representatives were $12.6 million and $13.7 million for the three months ended June 30, 2017 and 2016 , respectively. The amounts of payments to our Representatives were $24.5 million and $27.7 million for the six months ended June 30, 2017 and 2016 , respectively. The Company also sells extended warranties on parts for various lengths of time ranging from 6 months to 10 years. Revenue for these separately priced warranties is deferred and recognized on a straight-line basis over the separately priced warranty period.

Investments

Investments	6 Months Ended
	Jun. 30, 2017
Investments [Abstract]
Investments	Investments Certificates of Deposit – We held $5.5 million in certificates of deposit at June 30, 2017 and December 31, 2016 , respectively. At June 30, 2017 , the certificates of deposit bear interest ranging from 0.85% to 1.10% per annum and have various maturities ranging from less than one month to approximately 12 months . Investments Held to Maturity – Our investments held to maturity are comprised of $12.7 million of corporate notes and bonds with original maturities ranging from less than two months to approximately 10 months . The investments have moderate risk with S&P ratings ranging from AAA to BBB-. We record the amortized cost basis and accrued interest of the corporate notes and bonds in the Consolidated Balance Sheets. We record the interest and amortization of bond premium to interest income in the Consolidated Statements of Income. The following summarizes the amortized cost and estimated fair value of our investments held to maturity as of June 30, 2017 and December 31, 2016 : Amortized Cost Gross Unrealized Gain Gross Unrealized (Loss) Fair Value June 30, 2017: (in thousands) Current assets: Investments held to maturity $ 12,732 $ — $ (25 ) $ 12,707 Non current assets: Investments held to maturity — — — — Total $ 12,732 $ — $ (25 ) $ 12,707 December 31, 2016: Current assets: Investments held to maturity $ 14,083 $ — $ (12 ) $ 14,071 Non current assets: Investments held to maturity — — — — Total $ 14,083 $ — $ (12 ) $ 14,071

Accounts Receivable

Accounts Receivable	6 Months Ended
	Jun. 30, 2017
Receivables [Abstract]
Accounts Receivable	Accounts Receivable Accounts receivable and the related allowance for doubtful accounts are as follows: June 30, December 31, 2016 (in thousands) Accounts receivable $ 43,195 $ 43,091 Less: Allowance for doubtful accounts (81 ) (90 ) Total, net $ 43,114 $ 43,001 Three months ended Six months ended June 30, June 30, June 30, June 30, Allowance for doubtful accounts: (in thousands) Balance, beginning of period $ 274 $ 238 $ 90 $ 115 Provisions for losses on accounts receivables, net of recoveries (43 ) (165 ) 141 (42 ) Accounts receivable written off (150 ) — (150 ) — Balance, end of period $ 81 $ 73 $ 81 $ 73

Inventories

Inventories	6 Months Ended
	Jun. 30, 2017
Inventory Disclosure [Abstract]
Inventories	Inventories Inventories are valued at the lower of cost or market. Cost is determined by the first-in, first-out (“FIFO”) method. We establish an allowance for excess and obsolete inventories based on product line changes, the feasibility of substituting parts and the need for supply and replacement parts. June 30, December 31, 2016 (in thousands) Raw materials $ 55,930 $ 43,438 Work in process 2,867 2,279 Finished goods 5,920 3,017 64,717 48,734 Less: Allowance for excess and obsolete inventories (1,642 ) (1,382 ) Total, net $ 63,075 $ 47,352 The related changes in the allowance for excess and obsolete inventories account are as follows: Three months ended Six months ended June 30, June 30, June 30, June 30, Allowance for excess and obsolete inventories: (in thousands) Balance, beginning of period $ 1,442 $ 894 $ 1,382 $ 757 Provisions for excess and obsolete inventories 200 171 260 308 Inventories written off — — — — Balance, end of period $ 1,642 $ 1,065 $ 1,642 $ 1,065

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	6 Months Ended
	Jun. 30, 2017
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information	Supplemental Cash Flow Information Three months ended Six months ended June 30, June 30, June 30, June 30, Supplemental disclosures: (in thousands) Interest paid $ — $ — $ — $ — Income taxes paid $ 4,127 $ 10,329 $ 4,488 $ 10,847 Non-cash investing and financing activities: Non-cash capital expenditures $ (874 ) $ 1,047 $ 224 $ 1,312 Dividends declared 6,849 5,834 6,849 5,834

Warranties

Warranties	6 Months Ended
	Jun. 30, 2017
Guarantees [Abstract]
Warranties	Warranties The Company has warranties with various terms ranging from 18 months for parts to 25 years for certain heat exchangers. The Company has an obligation to replace parts or service its products if conditions under the warranty are met. A provision is made for estimated warranty costs at the time the related products are sold based upon the warranty period, historical trends, new products and any known identifiable warranty issues. The Company has been working on modifications and refinements to its warranty policy. These modifications more clearly define what qualifies as a warranty claim and puts a deadline for when claims may be submitted. This has increased our warranty reserve and increased our warranty expense for the three and six months ended June 30, 2017, as detailed below. Changes in the warranty accrual are as follows: Three months ended Six months ended June 30, June 30, June 30, June 30, Warranty accrual: (in thousands) Balance, beginning of period $ 7,812 $ 8,130 $ 7,936 $ 8,469 Payments made (2,312 ) (1,004 ) (3,654 ) (1,657 ) Provisions 3,102 1,328 4,320 1,642 Balance, end of period $ 8,602 $ 8,454 $ 8,602 $ 8,454 Warranty expense: $ 3,102 $ 1,328 $ 4,320 $ 1,642

Accrued Liabilities

Accrued Liabilities	6 Months Ended
	Jun. 30, 2017
Payables and Accruals [Abstract]
Accrued Liabilities	Accrued Liabilities Accrued liabilities are as follows: June 30, December 31, 2016 (in thousands) Warranty $ 8,602 $ 7,936 Due to representatives 10,152 9,907 Payroll 3,238 4,129 Profit sharing 2,156 1,967 Worker's compensation 661 580 Medical self-insurance 623 872 Customer prepayments 4,010 2,256 Donations 600 600 Employee benefits and other 4,251 3,693 Total $ 34,293 $ 31,940

Revolving Credit Facility

Revolving Credit Facility	6 Months Ended
	Jun. 30, 2017
Debt Disclosure [Abstract]
Revolving Credit Facility	Revolving Credit Facility Our revolving credit facility, which is provided by BOKF, NA dba Bank of Oklahoma, formerly known as Bank of Oklahoma, N.A. ("Bank of Oklahoma"), provides for maximum borrowings of $30.0 million . Under the line of credit, there is one standby letter of credit totaling $0.8 million . Borrowings available under the revolving credit facility at June 30, 2017 were $29.2 million . Interest on borrowings is payable monthly at LIBOR plus 2.5% . No fees are associated with the unused portion of the committed amount. We had no outstanding balance under the revolving credit facility at June 30, 2017 and December 31, 2016 . The termination date of the revolving credit facility is July 27, 2018. As of June 30, 2017 , we were in compliance with our financial covenants. These covenants require that we meet certain parameters related to our tangible net worth and total liabilities to tangible net worth ratio. At June 30, 2017 , our tangible net worth was $217.7 million and met the requirement of being at or above $125.0 million . Our total liabilities to tangible net worth ratio was 0.31 to 1, and met the requirement of not being above 2 to 1.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The provision (benefit) for income taxes consists of the following: Three months ended Six months ended June 30, June 30, June 30, June 30, (in thousands) Current $ 6,326 $ 8,371 $ 9,917 $ 14,867 Deferred (356 ) (821 ) 364 (1,851 ) $ 5,970 $ 7,550 $ 10,281 $ 13,016 The reconciliation of the Federal statutory income tax rate to the effective income tax rate is as follows: Three months ended Six months ended June 30, June 30, June 30, June 30, Federal statutory rate 35.0 % 35.0 % 35.0 % 35.0 % State income taxes, net of Federal benefit 4.5 4.9 4.0 5.0 Domestic manufacturing deduction (3.1 ) (3.5 ) (3.0 ) (3.5 ) Excess tax benefits (4.8 ) (1.7 ) (5.8 ) (2.9 ) Other (1.4 ) (0.8 ) (0.2 ) (0.5 ) Effective tax rate 30.2 % 33.9 % 30.0 % 33.1 % The Company's estimated annual 2017 effective tax rate, excluding discrete events, is approximately 36% . Additionally, as noted in Note 11, the Company early adopted ASU 2016-09, Improvements to Employee Share-Based Payment Accounting, applying the changes for excess tax benefits and tax deficiencies prospectively effective January 1, 2016. As a result, excess tax benefits and deficiencies are reported as an income tax benefit or expense on the statement of income rather than as a component of additional paid-in capital on the statement of equity. Excess tax benefits and deficiencies are treated as discrete items to the income tax provision in the reporting period in which they occur. We file income tax returns in the U.S., state and foreign income tax returns jurisdictions. We are subject to U.S. examinations for tax years 2013 to present, and to non-U.S. income tax examinations for the tax years of 2012 to present. In addition, we are subject to state and local income tax examinations for the tax years 2012 to present. The Company continues to evaluate its need to file returns in various state jurisdictions. Any interest or penalties would be recognized as a component of income tax expense.

Share-Based Compensation

Share-Based Compensation	6 Months Ended
	Jun. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	Share-Based Compensation On May 22, 2007, our stockholders adopted a Long-Term Incentive Plan (“LTIP”) which provided an additional 3.3 million shares that could be granted in the form of stock options, stock appreciation rights, restricted stock awards, performance units and performance awards. Since inception of the LTIP, non-qualified stock options and restricted stock awards were granted with the same vesting schedule as the previous plan. Under the LTIP, the exercise price of shares granted could not be less than 100% of the fair market value at the date of the grant. On May 24, 2016, our stockholders adopted the 2016 Long-Term Incentive Plan ("2016 Plan") which provides for approximately 3.8 million shares, comprised of 3.4 million new shares provided for under the 2016 Plan and approximately 0.4 million shares that were available for issuance under the previous LTIP, that are now authorized for issuance under the 2016 Plan, that can be granted in the form of stock options, stock appreciation rights, restricted stock awards, performance awards, dividend equivalent rights, and other awards. Under the 2016 Plan, the exercise price of shares granted may not be less than 100% of the fair market value at the date of the grant. The 2016 Plan will be administered by the Compensation Committee of the Board of Directors or such other committee of the Board of Directors as is designated by the Board of Directors (the “Committee”). Membership on the Committee shall be limited to independent directors. The Committee may delegate certain duties to one or more officers of the Company as provided in the 2016 Plan. The Committee will determine the persons to whom awards are to be made, determine the type, size and terms of awards, interpret the 2016 Plan, establish and revise rules and regulations relating to the 2016 Plan and make any other determinations that it believes necessary for the administration of the 2016 Plan. The compensation cost related to unvested stock options not yet recognized as of June 30, 2017 is $10.0 million and is expected to be recognized over a weighted-average period of 2.5 years. The following weighted average assumptions were used to determine the fair value of the stock options granted on the original grant date for expense recognition purposes for options granted during the six months ended June 30, 2017 and 2016 using a Black Scholes Model: Six months ended June 30, 2017 June 30, 2016 Director and Officers: Expected dividend rate $ 0.26 $ 0.22 Expected volatility 30.81 % 42.38 % Risk-free interest rate 1.90 % 2.02 % Expected life (in years) 5.0 8.0 Employees: Expected dividend rate $ 0.26 $ 0.22 Expected volatility 30.75 % 41.82 % Risk-free interest rate 1.89 % 1.76 % Expected life (in years) 5.0 8.0 The expected term of the options is based on evaluations of historical and expected future employee exercise behavior. The risk-free interest rate is based on the U.S. Treasury rates at the date of grant with maturity dates approximately equal to the expected life at the grant date. Volatility is based on historical volatility of our stock over time periods equal to the expected life at grant date. The following is a summary of stock options vested and exercisable as of June 30, 2017 : Range of Exercise Prices Number of Shares Weighted Average Remaining Contractual Life (in years) Weighted Average Exercise Price Intrinsic Value (in thousands) $4.54-$22.76 378,504 4.85 $ 10.98 $ 9,792 $23.57-$32.80 33,985 7.95 25.34 391 $32.85-$37.30 — — — — Total 412,489 5.10 $ 12.16 $ 10,183 The following is a summary of stock options vested and exercisable as of June 30, 2016 : Range of Exercise Prices Number of Shares Weighted Average Remaining Contractual Life (in years) Weighted Average Exercise Price Intrinsic Value (in thousands) $4.54-$8.65 344,958 5.06 $ 7.67 $ 6,843 $8.70-$22.76 37,505 7.39 15.77 440 $23.57-$28.27 7,664 8.66 23.57 30 Total 390,127 5.35 $ 8.76 $ 7,313 A summary of option activity under the plans is as follows: Options Shares Weighted Average Exercise Price Outstanding at December 31, 2016 1,450,704 $ 21.33 Granted 389,660 34.42 Exercised (154,368 ) 10.19 Forfeited or Expired (64,886 ) 30.51 Outstanding at June 30, 2017 1,621,110 $ 25.17 Exercisable at June 30, 2017 412,489 $ 12.16 The total intrinsic value of options exercised during the six months ended June 30, 2017 and 2016 was $4.0 million and $3.4 million , respectively. The cash received from options exercised during the six months ended June 30, 2017 and 2016 was $1.6 million and $1.3 million , respectively. The impact of these cash receipts is included in financing activities in the accompanying Consolidated Statements of Cash Flows. Since 2007, as part of the LTIP and since May 2016 as part of the 2016 Plan, the Compensation Committee of the Board of Directors has authorized and issued restricted stock awards to directors and key employees. Restricted stock awards granted to directors vest one-third each year. All other restricted stock awards vest at a rate of 20% per year. The fair value of restricted stock awards is based on the fair market value of AAON, Inc. common stock on the respective grant dates, reduced for the present value of dividends. These awards are recorded at their fair value on the date of grant and compensation cost is recorded using straight-line vesting over the service period. At June 30, 2017 , unrecognized compensation cost related to unvested restricted stock awards was approximately $8.3 million , which is expected to be recognized over a weighted average period of 2.0 years. A summary of the unvested restricted stock awards is as follows: Restricted stock Shares Weighted Fair Value Unvested at December 31, 2016 408,162 $ 20.47 Granted 123,151 33.96 Vested (121,956 ) 21.09 Forfeited (16,161 ) 22.86 Unvested at June 30, 2017 393,196 $ 24.41 A summary of share-based compensation is as follows: Three months ended Six months ended June 30, June 30, June 30, June 30, Grant date fair value of awards during the period: (in thousands) Options $ 633 $ 1,279 $ 3,507 $ 2,059 Restricted stock 1,582 1,043 4,182 2,942 Total $ 2,215 $ 2,322 $ 7,689 $ 5,001 Share-based compensation expense: Options $ 703 $ 404 $ 1,430 $ 741 Restricted stock 1,181 691 2,099 1,302 Total $ 1,884 $ 1,095 $ 3,529 $ 2,043 Income tax benefit/(deficiency) related to share-based compensation: Options $ 494 $ 417 $ 1,285 $ 1,130 Restricted stock 432 (33 ) 705 (1 ) Total $ 926 $ 384 $ 1,990 $ 1,129 In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting, which makes several modifications to Topic 718 including: accounting for excess tax benefits and deficiencies; classifying excess tax benefits on the statement of cash flows; accounting for forfeitures; classifying awards that permit share repurchases to satisfy statutory tax-withholding requirement; and classifying tax payments on behalf of employees on the statement of cash flows. The ASU became effective for interim and annual reporting periods beginning after December 31, 2016. We early adopted the ASU effective January 1, 2016. The Company previously applied a forfeiture rate to its share-based compensation expense and adjusted expense to actual as awards vested and/or were forfeited. Upon adoption of ASU 2016-09, the Company accounts for forfeitures as they occur, rather than estimating forfeitures as of an award's grant date. Tax payments made on behalf of an employee by repurchasing shares of stock are now shown separately as cash outflows from financing activities on the statement of cash flows. This provision was retrospectively adopted and prior period cash flows have been reclassified to conform with this presentation. Additionally, the Company retrospectively adopted the provision to classify excess tax benefits and deficiencies as cash flows from operating activities as part of cash payments for taxes on the statement of cash flows. Prior period cash flows have been reclassified to conform with this presentation. The following table displays the prior period quantitative effects on the consolidated financial statements: Three months ended Six months ended June 30, June 30, As Reported As Restated As Reported As Restated (in thousands, except share and per share data) Consolidated Statement of Income Income tax provision $ 7,934 $ 7,550 $ 14,145 $ 13,016 Net income 14,341 14,725 25,147 26,276 Earnings per share: Basic $ 0.27 $ 0.28 $ 0.47 $ 0.47 Diluted 0.27 0.27 0.47 0.47 Weighted average shares outstanding: Diluted 53,401,238 53,574,702 53,395,361 53,563,676 Consolidated Statement of Cash Flows Change in income taxes $ 5,162 $ 4,033

Earnings Per Share

Earnings Per Share	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share Basic net income per share is calculated by dividing net income by the weighted average number of shares of common stock outstanding during the period. Diluted net income per share assumes the conversion of all potentially dilutive securities and is calculated by dividing net income by the sum of the weighted average number of shares of common stock outstanding plus all potentially dilutive securities. Dilutive common shares consist primarily of stock options and restricted stock awards. ASU 2016-09 impacts the calculation of diluted weighted average shares under the treasury stock method as the Company no longer increases or decreases the assumed proceeds from an employee vesting in, or exercising, a share-based payment award by the amount of excess tax benefits or deficiencies taken to additional paid-in capital. Three months ended Six months ended June 30, June 30, June 30, June 30, (in thousands, except share and per share data) Numerator: Net income $ 13,794 $ 14,725 $ 24,011 $ 26,276 Denominator: Basic weighted average shares 52,615,366 53,036,009 52,624,782 53,028,224 Effect of dilutive stock options and restricted stock 535,768 538,693 551,643 535,452 Diluted weighted average shares 53,151,134 53,574,702 53,176,425 53,563,676 Earnings per share: Basic $ 0.26 $ 0.28 $ 0.46 $ 0.47 Diluted $ 0.26 $ 0.27 $ 0.45 $ 0.47 Anti-dilutive shares: Shares 760,438 504,954 772,202 498,043

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2017
Stockholders' Equity Note [Abstract]
Stockholders' Equity	Stockholders’ Equity Stock Repurchase - The Board has authorized three stock repurchase programs for the Company. The Company may purchase shares on the open market from time to time, up to a total of 5.7 million shares. The Board must authorize the timing and amount of these purchases. Effective May 24, 2016, the Board authorized up to $25.0 million in open market repurchases and on June 2, 2016, the Company executed a repurchase agreement in accordance with the rules and regulations of the SEC allowing the Company to repurchase an aggregate amount of $25.0 million or a total of approximately 2.0 million shares from the open market. The agreement expired on April 15, 2017. The Company also has a stock repurchase arrangement by which employee-participants in our 401(k) savings and investment plan are entitled to have shares in AAON, Inc. stock in their accounts sold to the Company. The maximum number of shares to be repurchased is contingent upon the number of shares sold by employee-participants. Lastly, the Company repurchases shares of AAON, Inc. stock from certain of its directors and employees for payment of statutory tax withholdings on stock transactions. Al1 other repurchases from directors or employees are contingent upon Board approval. All repurchases are done at current market prices. Our repurchase activity is as follows: Six Months Ended Inception to date 2017 2016 Program Shares Total $ $ per share Shares Total $ $ per share Shares Total $ $ per share Open market 8,676 $ 283,654 $ 32.69 10,230 $ 265,402 $ 25.94 3,843,495 $ 61,232,115 $ 15.93 401(k) 258,051 9,083,606 35.20 274,147 6,967,393 25.41 6,340,494 74,816,326 11.80 Directors and employees 30,158 1,066,450 35.36 17,128 440,828 25.74 1,903,790 16,730,059 8.79 Total 296,885 $ 10,433,710 $ 35.14 301,505 $ 7,673,623 $ 25.45 12,087,779 $ 152,778,500 $ 12.64 Dividends - At the discretion of the Board of Directors, we pay semi-annual cash dividends. Board approval is required to determine the date of declaration and amount for each semi-annual dividend payment. Our recent dividends are as follows: Declaration Date Record Date Payment Date Dividend per Share May 24, 2016 June 10, 2016 July 1, 2016 $ 0.11 November 9, 2016 December 2, 2016 December 23, 2016 $ 0.13 May 16, 2017 June 9, 2017 July 7, 2017 $ 0.13

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies We are subject to various claims and legal actions that arise in the ordinary course of business. We closely monitor these claims and legal actions and frequently consult with our legal counsel to determine whether they may, when resolved, have a material adverse effect on our financial position, results of operations or cash flows and we accrue and/or disclose loss contingencies as appropriate. We have concluded that the likelihood is remote that the ultimate resolution of any pending litigation or claims will be material or have a material adverse effect on the Company's business, financial position, results of operations or cash flows.

Basis of Presentation (Policies

Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2017
Basis of Presentation and Significant Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Because these estimates and assumptions require significant judgment, actual results could differ from those estimates and could have a significant impact on our results of operations, financial position and cash flows. We reevaluate our estimates and assumptions as needed, but at a minimum on a quarterly basis. The most significant estimates include, but are not limited to, the allowance for doubtful accounts, inventory reserves, warranty accrual, worker's compensation accrual, medical insurance accrual, income taxes and share-based compensation. Actual results could differ materially from those estimates.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Changes to U.S. GAAP are established by the Financial Accounting Standards Board ("FASB") in the form of Accounting Standards Updates ("ASUs") to the FASB's Accounting Standards Codification. We consider the applicability and impact of all ASUs. ASUs not listed below were assessed and determined to be either not applicable or are expected to have minimal impact on our consolidated financial statements and notes thereto. In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers , which 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. The ASU will replace most existing revenue recognition guidance in U.S. GAAP when it becomes effective. In August 2015, with the issuance of ASU 2015-14, the FASB amended the effective date for us to January 1, 2018. The following ASUs were issued in 2016 along with ASU 2014-09 with the same effective dates and transition requirements: • ASU 2016-08, Principal versus Agent Considerations (Reporting Revenue Gross versus Net) , which provides implementation guidance for Topic 606 on principal versus agent considerations. • ASU 2016-10, Identifying Performance Obligations and Licensing , which provides clarification for two aspects of Topic 606: identifying performance obligations and the licensing implementation guidance. • ASU 2016-12, Revenue from Contracts with Customers , which further amends Topic 606. • ASU 2016-20, Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers , which further amends Topic 606. The Company plans to adopt using the retrospective transition method. The Company has begun assessing the impact of ASU 2015-09 and believes the impact will not be material to the consolidated financial statements. Once we adopt ASU 2014-09, we do not anticipate that our internal control framework will materially change, but rather that existing internal controls will be modified and augmented, as necessary, to consider our new revenue recognition policy effective January 1, 2018. In January 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities , which will address certain aspects of recognition, measurement, presentation and disclosure of financial instruments. The ASU becomes effective in the annual reporting period beginning after December 31, 2017, including interim reporting periods. We do not expect ASU 2016-01 will have a material effect on our consolidated financial statements and notes thereto. In May 2017, the FASB issued ASU 2017-09, Scope of Modification Accounting , which addresses changes to the terms or conditions of a share-based payment award. The ASU becomes effective in the annual reporting period beginning after December 15, 2017, including interim reporting periods. We do not expect ASU 2017-09 will have a material effect on our consolidated financial statements and notes thereto. In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting, which makes several modifications to Topic 718 including: accounting for excess tax benefits and deficiencies; classifying excess tax benefits on the statement of cash flows; accounting for forfeitures; classifying awards that permit share repurchases to satisfy statutory tax-withholding requirement; and classifying tax payments on behalf of employees on the statement of cash flows. The ASU became effective for interim and annual reporting periods beginning after December 31, 2016. We early adopted the ASU effective January 1, 2016.

Investments (Tables)

Investments (Tables)	6 Months Ended
	Jun. 30, 2017
Investments [Abstract]
Amortized Cost and Estimated Fair Value of Investments Held to Maturity	The following summarizes the amortized cost and estimated fair value of our investments held to maturity as of June 30, 2017 and December 31, 2016 : Amortized Cost Gross Unrealized Gain Gross Unrealized (Loss) Fair Value June 30, 2017: (in thousands) Current assets: Investments held to maturity $ 12,732 $ — $ (25 ) $ 12,707 Non current assets: Investments held to maturity — — — — Total $ 12,732 $ — $ (25 ) $ 12,707 December 31, 2016: Current assets: Investments held to maturity $ 14,083 $ — $ (12 ) $ 14,071 Non current assets: Investments held to maturity — — — — Total $ 14,083 $ — $ (12 ) $ 14,071

Accounts Receivable (Tables)

Accounts Receivable (Tables)	6 Months Ended
	Jun. 30, 2017
Receivables [Abstract]
Accounts Receivable	June 30, December 31, 2016 (in thousands) Accounts receivable $ 43,195 $ 43,091 Less: Allowance for doubtful accounts (81 ) (90 ) Total, net $ 43,114 $ 43,001
Allowance for Doubtful Accounts	Three months ended Six months ended June 30, June 30, June 30, June 30, Allowance for doubtful accounts: (in thousands) Balance, beginning of period $ 274 $ 238 $ 90 $ 115 Provisions for losses on accounts receivables, net of recoveries (43 ) (165 ) 141 (42 ) Accounts receivable written off (150 ) — (150 ) — Balance, end of period $ 81 $ 73 $ 81 $ 73

Inventories (Tables)

Inventories (Tables)	6 Months Ended
	Jun. 30, 2017
Inventory Disclosure [Abstract]
Inventories	June 30, December 31, 2016 (in thousands) Raw materials $ 55,930 $ 43,438 Work in process 2,867 2,279 Finished goods 5,920 3,017 64,717 48,734 Less: Allowance for excess and obsolete inventories (1,642 ) (1,382 ) Total, net $ 63,075 $ 47,352
Inventories (Allowance)	The related changes in the allowance for excess and obsolete inventories account are as follows: Three months ended Six months ended June 30, June 30, June 30, June 30, Allowance for excess and obsolete inventories: (in thousands) Balance, beginning of period $ 1,442 $ 894 $ 1,382 $ 757 Provisions for excess and obsolete inventories 200 171 260 308 Inventories written off — — — — Balance, end of period $ 1,642 $ 1,065 $ 1,642 $ 1,065

Supplemental Cash Flow Inform25

Supplemental Cash Flow Information (Tables)	6 Months Ended
	Jun. 30, 2017
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information	Three months ended Six months ended June 30, June 30, June 30, June 30, Supplemental disclosures: (in thousands) Interest paid $ — $ — $ — $ — Income taxes paid $ 4,127 $ 10,329 $ 4,488 $ 10,847 Non-cash investing and financing activities: Non-cash capital expenditures $ (874 ) $ 1,047 $ 224 $ 1,312 Dividends declared 6,849 5,834 6,849 5,834

Warranties (Tables)

Warranties (Tables)	6 Months Ended
	Jun. 30, 2017
Guarantees [Abstract]
Warranty	Changes in the warranty accrual are as follows: Three months ended Six months ended June 30, June 30, June 30, June 30, Warranty accrual: (in thousands) Balance, beginning of period $ 7,812 $ 8,130 $ 7,936 $ 8,469 Payments made (2,312 ) (1,004 ) (3,654 ) (1,657 ) Provisions 3,102 1,328 4,320 1,642 Balance, end of period $ 8,602 $ 8,454 $ 8,602 $ 8,454 Warranty expense: $ 3,102 $ 1,328 $ 4,320 $ 1,642

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	6 Months Ended
	Jun. 30, 2017
Payables and Accruals [Abstract]
Accrued Liabilities	Accrued liabilities are as follows: June 30, December 31, 2016 (in thousands) Warranty $ 8,602 $ 7,936 Due to representatives 10,152 9,907 Payroll 3,238 4,129 Profit sharing 2,156 1,967 Worker's compensation 661 580 Medical self-insurance 623 872 Customer prepayments 4,010 2,256 Donations 600 600 Employee benefits and other 4,251 3,693 Total $ 34,293 $ 31,940

Income Taxes (Tables)

Income Taxes (Tables)	6 Months Ended
	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Schedule of Components of Income Tax Expense (Benefit)	The provision (benefit) for income taxes consists of the following: Three months ended Six months ended June 30, June 30, June 30, June 30, (in thousands) Current $ 6,326 $ 8,371 $ 9,917 $ 14,867 Deferred (356 ) (821 ) 364 (1,851 ) $ 5,970 $ 7,550 $ 10,281 $ 13,016
Schedule of Effective Income Tax Rate Reconciliation	The reconciliation of the Federal statutory income tax rate to the effective income tax rate is as follows: Three months ended Six months ended June 30, June 30, June 30, June 30, Federal statutory rate 35.0 % 35.0 % 35.0 % 35.0 % State income taxes, net of Federal benefit 4.5 4.9 4.0 5.0 Domestic manufacturing deduction (3.1 ) (3.5 ) (3.0 ) (3.5 ) Excess tax benefits (4.8 ) (1.7 ) (5.8 ) (2.9 ) Other (1.4 ) (0.8 ) (0.2 ) (0.5 ) Effective tax rate 30.2 % 33.9 % 30.0 % 33.1 %

Share-Based Compensation (Table

Share-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Stock Option Assumptions	The following weighted average assumptions were used to determine the fair value of the stock options granted on the original grant date for expense recognition purposes for options granted during the six months ended June 30, 2017 and 2016 using a Black Scholes Model: Six months ended June 30, 2017 June 30, 2016 Director and Officers: Expected dividend rate $ 0.26 $ 0.22 Expected volatility 30.81 % 42.38 % Risk-free interest rate 1.90 % 2.02 % Expected life (in years) 5.0 8.0 Employees: Expected dividend rate $ 0.26 $ 0.22 Expected volatility 30.75 % 41.82 % Risk-free interest rate 1.89 % 1.76 % Expected life (in years) 5.0 8.0
Summary of Stock Options Outstanding	The following is a summary of stock options vested and exercisable as of June 30, 2017 : Range of Exercise Prices Number of Shares Weighted Average Remaining Contractual Life (in years) Weighted Average Exercise Price Intrinsic Value (in thousands) $4.54-$22.76 378,504 4.85 $ 10.98 $ 9,792 $23.57-$32.80 33,985 7.95 25.34 391 $32.85-$37.30 — — — — Total 412,489 5.10 $ 12.16 $ 10,183 The following is a summary of stock options vested and exercisable as of June 30, 2016 : Range of Exercise Prices Number of Shares Weighted Average Remaining Contractual Life (in years) Weighted Average Exercise Price Intrinsic Value (in thousands) $4.54-$8.65 344,958 5.06 $ 7.67 $ 6,843 $8.70-$22.76 37,505 7.39 15.77 440 $23.57-$28.27 7,664 8.66 23.57 30 Total 390,127 5.35 $ 8.76 $ 7,313
Summary of Stock Option Activity	A summary of option activity under the plans is as follows: Options Shares Weighted Average Exercise Price Outstanding at December 31, 2016 1,450,704 $ 21.33 Granted 389,660 34.42 Exercised (154,368 ) 10.19 Forfeited or Expired (64,886 ) 30.51 Outstanding at June 30, 2017 1,621,110 $ 25.17 Exercisable at June 30, 2017 412,489 $ 12.16
Summary of Unvested Restricted Stock Awards	A summary of the unvested restricted stock awards is as follows: Restricted stock Shares Weighted Fair Value Unvested at December 31, 2016 408,162 $ 20.47 Granted 123,151 33.96 Vested (121,956 ) 21.09 Forfeited (16,161 ) 22.86 Unvested at June 30, 2017 393,196 $ 24.41
Summary of Grant Date Fair Value of Awards During Period	A summary of share-based compensation is as follows: Three months ended Six months ended June 30, June 30, June 30, June 30, Grant date fair value of awards during the period: (in thousands) Options $ 633 $ 1,279 $ 3,507 $ 2,059 Restricted stock 1,582 1,043 4,182 2,942 Total $ 2,215 $ 2,322 $ 7,689 $ 5,001
Summary of Share-Based Compensation Expense	Share-based compensation expense: Options $ 703 $ 404 $ 1,430 $ 741 Restricted stock 1,181 691 2,099 1,302 Total $ 1,884 $ 1,095 $ 3,529 $ 2,043
Summary of Income Tax Benefit Related to Share-Based Compensation	Income tax benefit/(deficiency) related to share-based compensation: Options $ 494 $ 417 $ 1,285 $ 1,130 Restricted stock 432 (33 ) 705 (1 ) Total $ 926 $ 384 $ 1,990 $ 1,129
Schedule of Quantitative Effects on Consolidated Financial Statements	The following table displays the prior period quantitative effects on the consolidated financial statements: Three months ended Six months ended June 30, June 30, As Reported As Restated As Reported As Restated (in thousands, except share and per share data) Consolidated Statement of Income Income tax provision $ 7,934 $ 7,550 $ 14,145 $ 13,016 Net income 14,341 14,725 25,147 26,276 Earnings per share: Basic $ 0.27 $ 0.28 $ 0.47 $ 0.47 Diluted 0.27 0.27 0.47 0.47 Weighted average shares outstanding: Diluted 53,401,238 53,574,702 53,395,361 53,563,676 Consolidated Statement of Cash Flows Change in income taxes $ 5,162 $ 4,033

Earnings Per Share (Tables)

Earnings Per Share (Tables)	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Earnings Per Share	Three months ended Six months ended June 30, June 30, June 30, June 30, (in thousands, except share and per share data) Numerator: Net income $ 13,794 $ 14,725 $ 24,011 $ 26,276 Denominator: Basic weighted average shares 52,615,366 53,036,009 52,624,782 53,028,224 Effect of dilutive stock options and restricted stock 535,768 538,693 551,643 535,452 Diluted weighted average shares 53,151,134 53,574,702 53,176,425 53,563,676 Earnings per share: Basic $ 0.26 $ 0.28 $ 0.46 $ 0.47 Diluted $ 0.26 $ 0.27 $ 0.45 $ 0.47 Anti-dilutive shares: Shares 760,438 504,954 772,202 498,043

Stockholders' Equity Stockholde

Stockholders' Equity Stockholders' Equity (Tables)	6 Months Ended
	Jun. 30, 2017
Stockholders' Equity Note [Abstract]
Schedule of Share Repurchases	Our repurchase activity is as follows: Six Months Ended Inception to date 2017 2016 Program Shares Total $ $ per share Shares Total $ $ per share Shares Total $ $ per share Open market 8,676 $ 283,654 $ 32.69 10,230 $ 265,402 $ 25.94 3,843,495 $ 61,232,115 $ 15.93 401(k) 258,051 9,083,606 35.20 274,147 6,967,393 25.41 6,340,494 74,816,326 11.80 Directors and employees 30,158 1,066,450 35.36 17,128 440,828 25.74 1,903,790 16,730,059 8.79 Total 296,885 $ 10,433,710 $ 35.14 301,505 $ 7,673,623 $ 25.45 12,087,779 $ 152,778,500 $ 12.64
Schedule of Dividends Payable	Our recent dividends are as follows: Declaration Date Record Date Payment Date Dividend per Share May 24, 2016 June 10, 2016 July 1, 2016 $ 0.11 November 9, 2016 December 2, 2016 December 23, 2016 $ 0.13 May 16, 2017 June 9, 2017 July 7, 2017 $ 0.13

Revenue Recognition (Details)

Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenue Recognition [Abstract]
Payments to representatives	$ 12.6	$ 13.7	$ 24.5	$ 27.7
Extended product warranties, minimum length			6 months
Extended product warranties, maximum length			10 years

Investments (Narrative) (Detail

Investments (Narrative) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Schedule of Investments [Line Items]
Certificates of deposits	$ 5,500	$ 5,500
Certificates of deposit interest rate, lower range	0.85%
Certificates of deposit interest rate, upper range	1.10%
Investments held to maturity	$ 12,732	$ 14,083
Minimum
Schedule of Investments [Line Items]
Certificates of deposit maturity dates	1 month
Investments maturity dates	2 months
Maximum
Schedule of Investments [Line Items]
Certificates of deposit maturity dates	12 months
Investments maturity dates	10 months

Investments (Investments Held t

Investments (Investments Held to Maturity) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Gain (Loss) on Investments [Line Items]
Amortized Cost	$ 12,732	$ 14,083
Gross Unrealized Gain	0	0
Gross Unrealized (Loss)	(25)	(12)
Fair Value	12,707	14,071
Current assets
Gain (Loss) on Investments [Line Items]
Amortized Cost	12,732	14,083
Gross Unrealized Gain	0	0
Gross Unrealized (Loss)	(25)	(12)
Fair Value	12,707	14,071
Non current assets
Gain (Loss) on Investments [Line Items]
Amortized Cost	0	0
Gross Unrealized Gain	0	0
Gross Unrealized (Loss)	0	0
Fair Value	$ 0	$ 0

Accounts Receivable (Details)

Accounts Receivable (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Receivables [Abstract]
Accounts receivable	$ 43,195	$ 43,091
Less: Allowance for doubtful accounts	(81)	(90)
Total, net	$ 43,114	$ 43,001

Accounts Receivable (Allowance)

Accounts Receivable (Allowance) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance, beginning of period	$ 274	$ 238	$ 90	$ 115
Provisions for losses on accounts receivables, net of recoveries	43	165	(141)	42
Accounts receivable written off, net of recoveries	(150)	0	(150)	0
Balance, end of period	$ 81	$ 73	$ 81	$ 73

Inventories (Components) (Detai

Inventories (Components) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015
Inventory Disclosure [Abstract]
Raw materials	$ 55,930		$ 43,438
Work in process	2,867		2,279
Finished goods	5,920		3,017
Inventory, gross	64,717		48,734
Less: Allowance for excess and obsolete inventories	(1,642)	$ (1,442)	(1,382)	$ (1,065)	$ (894)	$ (757)
Total, net	$ 63,075		$ 47,352

Inventories (Allowance) (Detail

Inventories (Allowance) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Inventory Valuation Reserves [Roll Forward]
Balance, beginning of period	$ 1,442	$ 894	$ 1,382	$ 757
Provisions for excess and obsolete inventories	200	171	260	308
Inventories written off	0	0	0	0
Balance, end of period	$ 1,642	$ 1,065	$ 1,642	$ 1,065

Supplemental Cash Flow Inform39

Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Supplemental disclosure:
Interest paid	$ 0	$ 0	$ 0	$ 0
Income taxes paid	4,127	10,329	4,488	10,847
Non-cash investing and financing activities:
Non-cash capital expenditures	(874)	1,047	224	1,312
Dividends declared	$ 6,849	$ 5,834	$ 6,849	$ 5,834

Warranties (Narrative) (Details

Warranties (Narrative) (Details)	6 Months Ended
	Jun. 30, 2017
Guarantees [Abstract]
Product warranty accrual, minimum length	18 months
Product warranty accrual, maximum length	25 years

Warranties (Details)

Warranties (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance, beginning of period	$ 7,812	$ 8,130	$ 7,936	$ 8,469
Payments made	(2,312)	(1,004)	(3,654)	(1,657)
Provisions	3,102	1,328	4,320	1,642
Balance, end of period	8,602	8,454	8,602	8,454
Warranty expense	$ 3,102	$ 1,328	$ 4,320	$ 1,642

Accrued Liabilities (Details)

Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Warranty	$ 8,602	$ 7,936
Due to representatives	10,152	9,907
Payroll	3,238	4,129
Profit sharing	2,156	1,967
Worker's compensation	661	580
Medical self-insurance	623	872
Customer prepayments	4,010	2,256
Donations	600	600
Employee benefits and other	4,251	3,693
Total	$ 34,293	$ 31,940

Revolving Credit Facility (Deta

Revolving Credit Facility (Details)	6 Months Ended
	Jun. 30, 2017USD ($)	Dec. 31, 2016USD ($)
Line of Credit Facility [Line Items]
Actual net worth for compliance	$ 217,700,000
Minimum net worth required for compliance	$ 125,000,000
Ratio of total liability to net worth	0.31
Maximum ratio of total liability to net worth for compliance	2
Borrowings outstanding under revolving credit facility	$ 0	$ 0
Fees associated with unused portion of committed amount	0
Revolving Credit Facility
Line of Credit Facility [Line Items]
Credit facility maximum borrowings	30,000,000
Standby letter of credit	800,000
Borrowings available under the revolving credit facility	$ 29,200,000
Frequency of periodic payment	monthly
Revolving Credit Facility | LIBOR
Line of Credit Facility [Line Items]
Stated percentage	2.50%

Income Taxes (Provision (Benefi

Income Taxes (Provision (Benefit) for Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Tax Disclosure [Abstract]
Current	$ 6,326	$ 8,371	$ 9,917	$ 14,867
Deferred	(356)	(821)	364	(1,851)
Provision (benefit) for income taxes	$ 5,970	$ 7,550	$ 10,281	$ 13,016

Income Taxes (Reconciliation of

Income Taxes (Reconciliation of Federal Statutory Income Tax Rate) (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Tax Disclosure [Abstract]
Federal statutory rate	35.00%	35.00%	35.00%	35.00%
State income taxes, net of Federal benefit	4.50%	4.90%	4.00%	5.00%
Domestic manufacturing deduction	(3.10%)	(3.50%)	(3.00%)	(3.50%)
Excess tax benefits	(4.80%)	(1.70%)	(5.80%)	(2.90%)
Other	(1.40%)	(0.80%)	(0.20%)	(0.50%)
Effective tax rate	30.20%	33.90%	30.00%	33.10%

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details)	6 Months Ended
	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Expected effective income tax rate for the year	36.00%

Share-Based Compensation (Narra

Share-Based Compensation (Narrative) (Details) - USD ($) $ in Millions	May 24, 2016	May 22, 2007	Jun. 30, 2017	Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock authorized to be issued under plan (in shares)	3,800,000
Unrecognized pre-tax compensation cost			$ 10
Weighted average recognition period (in years)			2 years 6 months
Total intrinsic value of options exercised during period			$ 4	$ 3.4
Cash received from options exercised during period			1.6	$ 1.3
2007 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock authorized to be issued under plan (in shares)	400,000	3,281,250
Exercise price of shares granted may not be less than fair market value (percentage)		100.00%
Unrecognized pre-tax compensation cost			$ 8.3
Weighted average recognition period (in years)			2 years
2016 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock authorized to be issued under plan (in shares)	3,400,000
Exercise price of shares granted may not be less than fair market value (percentage)	100.00%
Restricted Stock | 2007 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting period			20.00%
Director | Options Granted on or after May 25, 2004 | Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual vesting period			33.33%

Share-Based Compensation (Summa

Share-Based Compensation (Summary of Assumptions) (Details) - USD ($)	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Director and Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend rate	$ 0.26	$ 0.22
Expected volatility	30.81%	42.38%
Risk-free interest rate	1.90%	2.02%
Expected life	5 years	8 years
Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend rate	$ 0.26	$ 0.22
Expected volatility	30.75%	41.82%
Risk-free interest rate	1.89%	1.76%
Expected life	5 years	8 years

Share-Based Compensation (Sum49

Share-Based Compensation (Summary of Stock Options Outstanding) (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of shares vested and exercisable	412,489	390,127
Options vested and exercisable weighted average remaining contractual life	5 years 1 month 7 days	5 years 4 months 5 days
Options vested and exercisable weighted average exercise price	$ 12.16	$ 8.76
Options vested and exercisable intrinsic value	$ 10,183	$ 7,313
$4.54-$22.76
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower range	$ 4.54
Range of exercise prices, upper range	$ 22.76
Number of shares vested and exercisable	378,504
Options vested and exercisable weighted average remaining contractual life	4 years 10 months 6 days
Options vested and exercisable weighted average exercise price	$ 10.98
Options vested and exercisable intrinsic value	$ 9,792
$23.57-$32.80
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower range	$ 23.57
Range of exercise prices, upper range	$ 32.80
Number of shares vested and exercisable	33,985
Options vested and exercisable weighted average remaining contractual life	7 years 11 months 12 days
Options vested and exercisable weighted average exercise price	$ 25.34
Options vested and exercisable intrinsic value	$ 391
$32.85-$37.30
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower range	$ 32.85
Range of exercise prices, upper range	$ 37.30
Number of shares vested and exercisable	0
Options vested and exercisable weighted average exercise price	$ 0
Options vested and exercisable intrinsic value	$ 0
$4.54-$8.65
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower range		$ 4.54
Range of exercise prices, upper range		$ 8.65
Number of shares vested and exercisable		344,958
Options vested and exercisable weighted average remaining contractual life		5 years 22 days
Options vested and exercisable weighted average exercise price		$ 7.67
Options vested and exercisable intrinsic value		$ 6,843
$8.70-$22.76
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower range		$ 8.70
Range of exercise prices, upper range		$ 22.76
Number of shares vested and exercisable		37,505
Options vested and exercisable weighted average remaining contractual life		7 years 4 months 21 days
Options vested and exercisable weighted average exercise price		$ 15.77
Options vested and exercisable intrinsic value		$ 440
$23.57-$28.27
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower range		$ 23.57
Range of exercise prices, upper range		$ 28.27
Number of shares vested and exercisable		7,664
Options vested and exercisable weighted average remaining contractual life		8 years 7 months 27 days
Options vested and exercisable weighted average exercise price		$ 23.57
Options vested and exercisable intrinsic value		$ 30

Share-Based Compensation (Sum50

Share-Based Compensation (Summary of Stock Option Activity) (Details) - $ / shares	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Shares [Roll Forward]
Outstanding, beginning of period (in shares)	1,450,704
Granted (in shares)	389,660
Exercised (in shares)	(154,368)
Forfeited or Expired (in shares)	(64,886)
Outstanding, end of period (in shares)	1,621,110
Exercisable, end of period (in shares)	412,489	390,127
Weighted Average Exercise Price [Roll Forward]
Outstanding, beginning of period (weighted average exercise price)	$ 21.33
Granted (weighted average exercise price)	34.42
Exercised (weighted average exercise price)	10.19
Forfeited or Expired (weighted average exercise price)	30.51
Outstanding, end of period (weighted average exercise price)	25.17
Exercisable, end of period (weighted average exercise price)	$ 12.16	$ 8.76

Share-Based Compensation (Sum51

Share-Based Compensation (Summary of Unvested Restricted Stock Awards) (Details)	6 Months Ended
	Jun. 30, 2017$ / sharesshares
Shares [Roll Forward]
Unvested, beginning of period (in shares) | shares	408,162
Granted (in shares) | shares	123,151
Vested (in shares) | shares	(121,956)
Forfeited (in shares) | shares	(16,161)
Unvested, end of period (in shares) | shares	393,196
Weighted Average Grant Date Fair Value [Roll Forward]
Unvested, beginning of period (weighted average grant date fair value) | $ / shares	$ 20.47
Granted (weighted average grant date fair value) | $ / shares	33.96
Vested (weighted average grant date fair value) | $ / shares	21.09
Forfeited (weighted average grant date fair value) | $ / shares	22.86
Unvested, end of period (weighted average grant date fair value) | $ / shares	$ 24.41

Share-Based Compensation (Sum52

Share-Based Compensation (Summary of Grant Date Fair Value of Awards) (Details) - USD ($) $ in Thousands	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]
Options	$ 633	$ 1,279	$ 3,507	$ 2,059
Restricted stock	1,582	1,043	4,182	2,942
Total	$ 2,215	$ 2,322	$ 7,689	$ 5,001

Share-Based Compensation (Sum53

Share-Based Compensation (Summary of Share-Based Compensation Expense) (Details) - USD ($) $ in Thousands	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]
Options	$ 703	$ 404	$ 1,430	$ 741
Restricted stock	1,181	691	2,099	1,302
Total	$ 1,884	$ 1,095	$ 3,529	$ 2,043

Share-Based Compensation (Sum54

Share-Based Compensation (Summary of Income Tax Benefit Related to Share-Based Compensation) (Details) - USD ($) $ in Thousands	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]
Options	$ 494	$ 417	$ 1,285	$ 1,130
Restricted stock	432	(33)	705	(1)
Total	$ 926	$ 384	$ 1,990	$ 1,129

Share-Based Compensation Share-

Share-Based Compensation Share-Based Compensation (Summary of Quantitative Effects on Consolidated Financial Statements) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Income tax provision	$ 5,970	$ 7,550	$ 10,281	$ 13,016
Net income	$ 13,794	$ 14,725	$ 24,011	$ 26,276
Basic (usd per share)	$ 0.26	$ 0.28	$ 0.46	$ 0.47
Diluted (usd per share)	$ 0.26	$ 0.27	$ 0.45	$ 0.47
Diluted weighted average shares (in shares)	53,151,134	53,574,702	53,176,425	53,563,676
Change in income taxes			$ 5,430	$ 4,033
As Reported
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Income tax provision		7,934		14,145
Net income		$ 14,341		$ 25,147
Basic (usd per share)		$ 0.27		$ 0.47
Diluted (usd per share)		$ 0.27		$ 0.47
Diluted weighted average shares (in shares)		53,401,238		53,395,361
Change in income taxes				$ 5,162

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Earnings Per Share [Abstract]
Net income	$ 13,794	$ 14,725	$ 24,011	$ 26,276
Basic weighted average shares (in shares)	52,615,366	53,036,009	52,624,782	53,028,224
Effect of dilutive stock options and restricted stock (in shares)	535,768	538,693	551,643	535,452
Diluted weighted average shares (in shares)	53,151,134	53,574,702	53,176,425	53,563,676
Basic (usd per share)	$ 0.26	$ 0.28	$ 0.46	$ 0.47
Diluted (usd per share)	$ 0.26	$ 0.27	$ 0.45	$ 0.47
Anti-dilutive shares (in shares)	760,438	504,954	772,202	498,043

Stockholders' Equity (Details)

Stockholders' Equity (Details) - USD ($)	May 16, 2017	Nov. 09, 2016	May 24, 2016	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2017	Jun. 30, 2017	Jun. 02, 2016	May 19, 2015
Schedule of Shareholders' Equity [Line Items]
Stock repurchased during period (in shares)						296,885	301,505			12,087,779
Aggregate price of shares repurchased since inception						$ 10,433,710	$ 7,673,623			$ 152,778,500
Average price of shares repurchased since inception (per share)						$ 35.14	$ 25.45			$ 12.64
Cash dividends declared per common share				$ 0.13	$ 0.11	$ 0.13	$ 0.11
Dividend Declared
Schedule of Shareholders' Equity [Line Items]
Cash dividends declared per common share	$ 0.13	$ 0.13	$ 0.11
2010 Stock Repurchase Program
Schedule of Shareholders' Equity [Line Items]
Stock repurchase program amount authorized (in shares)											2,000,000	5,700,000
Stock Repurchase Program, Authorized Amount			$ 25,000,000								$ 25,000,000
Stock repurchased during period (in shares)						8,676	10,230	3,843,495
Aggregate price of shares repurchased since inception						$ 283,654	$ 265,402	$ 61,232,115
Average price of shares repurchased since inception (per share)						$ 32.69	$ 25.94	$ 15.93
2005 401(k) Stock Repurchase Program
Schedule of Shareholders' Equity [Line Items]
Stock repurchased during period (in shares)						258,051	274,147			6,340,494
Aggregate price of shares repurchased since inception						$ 9,083,606	$ 6,967,393			$ 74,816,326
Average price of shares repurchased since inception (per share)						$ 35.20	$ 25.41			$ 11.80
2006 Director and Officer Repurchase Program
Schedule of Shareholders' Equity [Line Items]
Stock repurchased during period (in shares)						30,158	17,128		1,903,790
Aggregate price of shares repurchased since inception						$ 1,066,450	$ 440,828		$ 16,730,059
Average price of shares repurchased since inception (per share)						$ 35.36	$ 25.74		$ 8.79