Spok (SPOK) 10-Q 27 Jul 17 2017 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2017	Jul. 21, 2017
Document Document And Entity Information [Abstract]
Entity Registrant Name	Spok Holdings, Inc
Entity Central Index Key	1,289,945
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-Q
Document Period End Date	Jun. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding (shares)		19,977,318

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 107,151	$ 125,816
Accounts receivable, net	24,452	23,666
Prepaid expenses and other	7,669	4,384
Inventory	1,642	1,996
Total current assets	140,914	155,862
Non-current assets:
Property and equipment, net	13,889	12,818
Goodwill	133,031	133,031
Intangible assets, net	9,166	10,803
Deferred income tax assets	72,018	73,068
Other non-current assets	2,204	2,505
Total non-current assets	230,308	232,225
TOTAL ASSETS	371,222	388,087
Current liabilities:
Accounts payable	1,554	1,909
Accrued compensation and benefits	11,310	13,268
Accrued dividends payable	342	5,140
Accrued taxes	2,658	4,132
Deferred revenue	31,807	29,145
Other current liabilities	2,820	2,733
Total current liabilities	50,491	56,327
Non-current liabilities:
Deferred revenue	651	752
Other non-current liabilities	8,570	8,921
Total non-current liabilities	9,221	9,673
TOTAL LIABILITIES	59,712	66,000
COMMITMENTS AND CONTINGENCIES
STOCKHOLDERS' EQUITY:
Preferred stock	0	0
Common stock	2	2
Additional paid-in capital	96,943	104,810
Retained earnings	214,565	217,275
TOTAL STOCKHOLDERS’ EQUITY	311,510	322,087
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 371,222	$ 388,087

Condensed Consolidated Statemen

Condensed 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
Revenue:
Wireless	$ 25,639	$ 27,859	$ 51,499	$ 56,031
Software	16,686	16,776	32,270	33,992
Total revenue	42,325	44,635	83,769	90,023
Operating expenses:
Cost of revenue	7,190	7,513	14,226	15,528
Research and development	4,662	3,212	8,767	6,120
Service, rental and maintenance	7,944	8,187	16,010	16,492
Selling and marketing	5,329	6,429	11,251	12,957
General and administrative	11,939	10,439	23,649	20,946
Depreciation, amortization and accretion	2,851	3,235	6,074	6,558
Total operating expenses	39,915	39,015	79,977	78,601
Operating income	2,410	5,620	3,792	11,422
Interest income	154	61	276	109
Other income	89	104	58	357
Income before income tax expense	2,653	5,785	4,126	11,888
Income tax expense	(1,155)	(2,334)	(1,774)	(4,993)
Net income	$ 1,498	$ 3,451	$ 2,352	$ 6,895
Basic net income per common share (usd per share)	$ 0.07	$ 0.17	$ 0.12	$ 0.33
Diluted net income per common share (usd per share)	$ 0.07	$ 0.17	$ 0.11	$ 0.33
Basic weighted average common shares outstanding (shares)	20,353,801	20,568,058	20,441,781	20,637,070
Diluted weighted average common shares outstanding (shares)	20,366,102	20,568,058	20,508,473	20,637,070
Cash dividends declared per common share (usd per share)	$ 0.125	$ 0.125	$ 0.25	$ 0.25

Condensed Consolidated Stateme4

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash flows provided by operating activities:
Net income	$ 2,352	$ 6,895
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization and accretion	6,074	6,558
Deferred income tax expense	1,069	4,346
Stock based compensation	1,953	1,368
Provision for doubtful accounts, service credits and other	458	321
Adjustment of non-cash transaction taxes	(700)	(169)
Changes in assets and liabilities:
Accounts receivable	(1,242)	(1,421)
Prepaid expenses, inventory, intangibles and other assets	(2,684)	1,197
Accounts payable, accrued liabilities and other	(3,175)	(342)
Deferred revenue	2,561	1,126
Net cash provided by operating activities	6,666	19,879
Cash flows used in investing activities:
Purchase of property and equipment, net of proceeds from disposals of property and equipment	(5,198)	(2,981)
Net cash used in investing activities	(5,198)	(2,981)
Cash flows used in financing activities:
Cash distributions to stockholders	(10,239)	(5,150)
Purchase of common stock (including commissions), net of proceeds from issuance of common stock	(9,894)	(5,985)
Net cash used in financing activities	(20,133)	(11,135)
Net (decrease) increase in cash and cash equivalents	(18,665)	5,763
Cash and cash equivalents, beginning of period	125,816	111,332
Cash and cash equivalents, end of period	107,151	117,095
Supplemental disclosure:
Income taxes paid	$ 1,964	$ 598

Organization and Significant Ac

Organization and Significant Accounting Policies	6 Months Ended
	Jun. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Significant Accounting Policies	ORGANIZATION AND SIGNIFICANT ACCOUNTING POLICIES Spok Holdings, Inc. (NASDAQ: SPOK) ("Spok" or the "Company") through its wholly-owned subsidiary Spok, Inc., is the global leader in healthcare communications. We deliver clinical information to care teams when and where it matters most to improve patient outcomes. Many hospitals rely on the Spok Care Connect platform to enhance workflows for clinicians, support administrative compliance, and provide a better experience for patients. Our customers send over 100 million messages each month through their Spok solutions. We offer a focused suite of unified critical communication solutions that include call center operations, clinical alerting and notifications, one-way and advanced two-way wireless messaging services, mobile communications and public safety solutions. We provide one-way and advanced two-way wireless messaging services including information services throughout the United States. These services are offered on a local, regional and nationwide basis employing digital networks. One-way messaging consists of numeric and alphanumeric messaging services. Numeric messaging services enable subscribers to receive messages that are composed entirely of numbers, such as a phone number, while alphanumeric messages may include numbers and letters, which enable subscribers to receive text messages. Two-way messaging services enable subscribers to send and receive messages to and from other wireless messaging devices, including pagers, personal digital assistants and personal computers. We also offer voice mail, personalized greeting, message storage and retrieval, and equipment loss and/or maintenance protection to both one-way and two-way messaging subscribers. These services are commonly referred to as wireless messaging and information services. We also develop, sell and support enterprise-wide systems for hospitals and other organizations needing to automate, centralize and standardize mission critical communications. These solutions are used for contact centers, clinical alerting and notification, mobile communications and messaging and for public safety notifications. These areas of market focus complement the market focus of our wireless services outlined above. These products and services are commonly referred to as software solutions and services. Basis of Presentation The accompanying condensed consolidated financial statements include our accounts and the accounts of our wholly-owned direct and indirect subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation. Our condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) and the rules and regulations of the United States Securities and Exchange Commission (the “SEC”). In management's opinion, the unaudited condensed consolidated financial statements include all adjustments and accruals that are necessary for a fair presentation of the results of all interim periods reported herein and all such adjustments are of a normal, recurring nature. Amounts shown on the condensed consolidated statements of income within the operating expense categories of cost of revenue; research and development; service, rental and maintenance; selling and marketing; and general and administrative are recorded exclusive of depreciation, amortization and accretion. These items are shown separately on the condensed consolidated statements of income within operating expenses. Foreign currency translation adjustments were immaterial and are not presented separately in our condensed consolidated financial statements and consequently no statements of comprehensive income are presented. Certain prior period amounts in the condensed consolidated financial statements have been reclassified to conform to the current period's presentation. These reclassifications had no effect on the reported results of operations. In the fourth quarter 2016, the Company concluded that it was appropriate to separately state those operating expenses related to research and development. Previously those expenses had been classified under the Service, Rental and Maintenance operating category. Corresponding reclassifications were made to the condensed consolidated statements of income for the three and six months ended June 30, 2016 . This change in classification has no effect on the previously reported condensed consolidated statements of income for any period. The financial information included herein, other than the condensed consolidated balance sheet as of December 31, 2016 , is unaudited. The condensed consolidated balance sheet at December 31, 2016 has been derived from, but does not include, all the disclosures contained in the audited consolidated financial statements as of and for the year ended December 31, 2016 . These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and accompanying notes included in the Company's Annual Report on Form 10-K for the year ended December 31, 2016 (the “ 2016 Annual Report”). The condensed consolidated statements of income for the interim periods presented are not necessarily indicative of the results that may be expected for a full year. Use of Estimates The preparation of these condensed consolidated financial statements requires management to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues, expenses and related disclosures. On an on-going basis, we evaluate estimates and assumptions, including but not limited to those related to the impairment of long-lived assets, intangible assets subject to amortization and goodwill, accounts receivable allowances, revenue recognition, depreciation expense, asset retirement obligations, severance and income taxes. We base our estimates on historical experience and various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.

Risks and Other Important Facto

Risks and Other Important Factors	6 Months Ended
	Jun. 30, 2017
Risks and Uncertainties [Abstract]
Risks and Other Important Factors	RISKS AND OTHER IMPORTANT FACTORS See “Item 1A. Risk Factors” of Part II of this Quarterly Report on Form 10-Q (“Quarterly Report”) and "Item 1A. Risk Factors" of Part I of the 2016 Annual Report, which describes key risks associated with our operations and industry.

Recent and Pending Accounting S

Recent and Pending Accounting Standards	6 Months Ended
	Jun. 30, 2017
Accounting Changes and Error Corrections [Abstract]
Recent and Pending Accounting Standards	RECENT AND PENDING ACCOUNTING STANDARDS Revenue In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers. Since this ASU was issued, the FASB has issued several updates including ASU No. 2015-14 in July 2015 which delayed the effective date, ASU No. 2016-08 in March 2016 which updated guidance related to principal versus agent considerations, ASU No. 2016-10 in April 2016 which updated guidance related to the identification of performance obligations, ASU No. 2016-12 in May 2016 which updated guidance related to scope improvements and practical expedients and ASU No. 2016-20 which provided technical corrections and improvements but did not update guidance issued in prior updates. The effective date is January 1, 2018, and while early adoption to the original effective date of January 1, 2017 is permitted, we have elected not to early adopt. ASU No. 2014-09 creates a five-step model that requires companies to exercise judgment when considering all relevant facts and circumstances in the determination of when and how revenue is recognized. The two permitted transition methods under the new standard are the full retrospective method, in which case the standard would be applied to each prior reporting period presented, or the modified retrospective method, in which case the cumulative effect of applying the standard would be recognized at the date of initial application. We have completed our review of the acceptable transition methods and have selected the modified retrospective approach. We currently believe the modified retrospective approach will have a material impact on both deferred revenue and retained earnings in our 2018 consolidated financial statements. We currently believe the standard will materially impact our revenue recognition on a going-forward basis once adopted. While we continue to assess the potential impacts of this standard, we currently believe that the most significant impact relates to our accounting for software license revenue. We expect software license revenue to be recognized at the time of shipment rather than over a combined service period or term period. Due to the nuances of certain contracts the actual revenue recognition treatment required under the standard will be dependent on contract-specific terms and may vary in some instances from recognition at the time that software is made available to the customer. Leases In February 2016, the FASB issued ASU No. 2016-02, Leases. The new standard establishes a right of use (“ROU”) model that requires a lessee to record a ROU asset and a lease liability on the balance sheet for all leases with terms longer than twelve months. Leases will be classified as either financing or operating with the classification affecting the pattern of expense recognition in the income statement. ASU No. 2016-02 will be effective for fiscal years beginning on January 1, 2019, including the related interim periods and early adoption of the standard is permitted. A modified retrospective transition approach is required for capital and operating leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements, with certain practical expedients available. While we are still evaluating the impact of the potential new standard on our consolidated financial statements, we expect that upon adoption we will recognize ROU assets and lease liabilities and that the amounts could be material. Goodwill In January 2017, the FASB issued ASU No. 2017-04, Intangibles - Goodwill and Other: Simplifying the Test for Goodwill Impairment. The new standard simplifies how an entity tests for goodwill by eliminating Step 2 from the goodwill impairment test. Step 2 measured a goodwill impairment loss by comparing the implied fair value of a reporting unit's goodwill with the carrying amount of that goodwill. By eliminating Step 2 an entity must now record an impairment to goodwill based on an analysis of the fair value of a reporting unit as compared to its carrying amount. An impairment charge is recognized for the amount that the carrying value exceeds the reporting unit's fair value. ASU No. 2017-04 will be effective for fiscal years beginning on January 1, 2020, including interim periods within those fiscal years, and early adoption as of January 1, 2017 is permitted. All changes are to be accounted for on a prospective basis upon adoption. We do not believe adoption of ASU No. 2017-04 will have a material impact on our consolidated financial statements. We have not yet determined whether we will early adopt ASU No. 2017-04.

Consolidated Financial Statemen

Consolidated Financial Statement Components	6 Months Ended
	Jun. 30, 2017
Supplemental Financial Statement Components [Abstract]
Consolidated Financial Statement Components	CONSOLIDATED FINANCIAL STATEMENT COMPONENTS Prepaid Expenses and Other Prepaid expenses and other consisted of the following as of the date stated: (Dollars in thousands) June 30, 2017 December 31, 2016 Prepaid repairs and maintenance $ 2,312 $ 1,561 Prepaid rent 1,559 208 Prepaid commissions 1,469 594 Prepaid taxes 792 100 Other prepaid expenses 1,537 1,921 Total prepaid expenses and other $ 7,669 $ 4,384 Depreciation, Amortization and Accretion Depreciation, amortization and accretion expenses consisted of the following for the periods stated: For the Three Months Ended June 30, For the Six Months Ended June 30, (Dollars in thousands) 2017 2016 2017 2016 Depreciation Leasehold improvements $ 75 $ 52 $ 125 $ 98 Asset retirement costs (97 ) (69 ) (195 ) (140 ) Paging and computer equipment 2,028 1,992 4,087 3,995 Furniture, fixtures and vehicles 76 69 141 148 Total depreciation 2,082 2,044 4,158 4,101 Amortization 629 1,035 1,636 2,146 Accretion 140 156 280 311 Total depreciation, amortization and accretion expense $ 2,851 $ 3,235 $ 6,074 $ 6,558 Accounts Receivable, Net Accounts receivable was recorded net of an allowance of $ 1.1 million at June 30, 2017 and December 31, 2016 . Property and Equipment, Net Property and equipment, net consisted of the following as of the date stated: (Dollars in thousands) Useful Life June 30, 2017 December 31, 2016 Leasehold improvements lease term $ 4,051 $ 3,843 Asset retirement costs 1-5 3,289 3,263 Paging and computer equipment 1-5 112,800 113,175 Furniture, fixtures and vehicles 3-5 4,447 2,852 Total property and equipment 124,587 123,133 Accumulated depreciation (110,698 ) (110,315 ) Total property and equipment, net $ 13,889 $ 12,818 Other Current Liabilities Other current liabilities consisted of the following as of the date stated: (Dollars in thousands) June 30, 2017 December 31, 2016 Accrued outside services $ 1,057 $ 975 Accrued accounting and legal 678 467 Accrued network costs 644 773 Deferred rent and other 255 433 Asset retirement obligations 186 85 Total other current liabilities $ 2,820 $ 2,733 Other Non-Current Liabilities Other non-current liabilities consisted of the following as of the date stated: (Dollars in thousands) June 30, 2017 December 31, 2016 Asset retirement obligations $ 7,548 $ 7,472 Deferred rent and other 893 942 Dividends payable 129 507 Total other non-current liabilities $ 8,570 $ 8,921

Intangible Assets, Net

Intangible Assets, Net	6 Months Ended
	Jun. 30, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets, Net	INTANGIBLE ASSETS, NET Intangible Assets Amortizable intangible assets at June 30, 2017 related primarily to customer relationships that resulted from our acquisition of Amcom Software, Inc. in 2011. Such intangibles are being amortized over a period of ten years . The net consolidated balance of intangible assets consisted of the following at June 30, 2017 : June 30, 2017 (Dollars in thousands) Useful Life Gross Carrying Accumulated Net Balance Customer relationships 10 $ 25,002 $ (15,836 ) $ 9,166 Total amortizable intangible assets 10 $ 25,002 $ (15,836 ) $ 9,166 Estimated amortization of intangible assets for future periods was as follows: (Dollars in thousands) For the remaining six months ending December 31, 2017 $ 1,250 For the year ending December 31: 2018 2,500 2019 2,500 2020 2,500 2021 416 Total amortizable intangible assets $ 9,166

Asset Retirement Obligations

Asset Retirement Obligations	6 Months Ended
	Jun. 30, 2017
Asset Retirement Obligation Disclosure [Abstract]
Asset Retirement Obligations	ASSET RETIREMENT OBLIGATIONS The components of the changes in the asset retirement obligation liabilities were: (Dollars in thousands) Short-Term Long-Term Total Balance at January 1, 2017 $ 85 $ 7,472 $ 7,557 Accretion 4 276 280 Amounts paid (129 ) — (129 ) Asset additions recorded, net — 26 26 Reclassifications 226 (226 ) — Balance at June 30, 2017 $ 186 $ 7,548 $ 7,734 The balances above were included within other current liabilities and other non-current liabilities, respectively, at June 30, 2017 . Increases and reductions other than accretion, reclassification and amounts paid primarily relate to changes in estimate of the underlying liability, specifically as it relates to updates in estimated costs to remove a transmitter and the estimated timing of removal. The cost associated with the estimated removal costs and timing refinements due to ongoing network rationalization activities is expected to accrete to a total liability of $9.0 million . The total estimated liability is based on the transmitter locations remaining after we have consolidated the number of networks we operate and assume the underlying leases continue to be renewed to that future date. Accretion expense was $0.3 million for the six months ended June 30, 2017 and 2016 . Accretion expense related solely to asset retirement obligations and was recorded based on the interest method.

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2017
Equity [Abstract]
Stockholders' Equity	STOCKHOLDERS' EQUITY General Our authorized capital stock consists of 75 million shares of common stock, par value $0.0001 per share, and 25 million shares of preferred stock, par value $0.0001 per share. At June 30, 2017 and December 31, 2016 , we had no stock options outstanding. At June 30, 2017 and December 31, 2016 , there were 19,972,094 and 20,525,614 shares of common stock outstanding, respectively, and no shares of preferred stock outstanding. Changes in Stockholders' Equity Changes in stockholders’ equity for the six months ended June 30, 2017 consisted of the following: (Dollars in thousands) Balance at January 1, 2017 $ 322,087 Net income for the six months ended June 30, 2017 2,352 Cash dividends declared (5,221 ) Common stock repurchase program (10,024 ) Amortization of stock based compensation 1,953 Other 363 Balance at June 30, 2017 $ 311,510 Dividends The following table details our cash dividend payments made in 2017 . Cash dividends paid as disclosed in the condensed consolidated statements of cash flows for the six months ended June 30, 2017 and 2016 include previously declared cash dividends on shares of vested restricted common stock ("restricted stock") issued to our non-executive directors and dividends related to vested restricted stock units ("RSUs") issued to eligible employees. Cash dividends on RSUs and restricted stock have been accrued and are paid when the applicable vesting conditions are met. Accrued cash dividends on forfeited restricted stock and RSUs are also forfeited. Declaration Date Record Date Payment Date Per Share Amount Total Payment (1) (Dollars in thousands) December 20, 2016 January 4, 2017 January 17, 2017 $ 0.250 $ 5,128 March 1, 2017 March 17, 2017 March 30, 2017 0.125 2,566 April 26, 2017 May 23, 2017 June 23, 2017 0.125 2,545 Total $ 0.500 $ 10,239 (1) The total payment reflects the cash dividends paid in relation to common stock and vested restricted stock. On July 26, 2017, our Board of Directors declared a regular quarterly cash dividend of $0.125 per share of common stock with a record date of August 18, 2017, and a payment date of September 8, 2017. This cash dividend of approximately $2.5 million will be paid from available cash on hand. Common Stock Repurchase Program On April 26, 2017, the Company's Board of Directors authorized the repurchase of up to $10.0 million of the Company's common stock through 2017 on the open market or in privately negotiated transactions. The Company used the entire $10.0 million of repurchase authority by June 30, 2017. The following table presents information with respect to purchases made by the Company during the six months ended June 30, 2017 : Period Total Number of Shares Purchased Average Price Paid Per Share Total Number of Shares Purchased as Part of the Publicly Announced Plans or Programs Approximate Dollar Value of Shares That May Yet Be Purchased Under the Publicly Announced Plans or Programs (Dollars in thousands) Beginning Balance $ 10,000 Three Months Ended June 30, 2017 572,550 17.47 572,550 — Total 572,550 $ 17.47 572,550 Net Income per Common Share Basic net income per common share is computed on the basis of the weighted average common shares outstanding. Diluted net income per common share is computed on the basis of the weighted average common shares outstanding plus the effect of all potentially dilutive common shares including outstanding restricted stock and RSUs, which are treated as contingently issuable shares, using the “treasury stock” method. The Company has determined, based on the provisions of the 2015 Long-Term Incentive Plan ("2015 LTIP"), that unvested RSUs do not currently meet, nor have they met since issuance, the criteria to be considered dilutive. Therefore, we have excluded them from the calculation of both diluted net income per common share as well as the diluted weighted average shares of common stock and common stock equivalents for the three and six months ended June 30, 2017 and removed them from the comparative information for the three and six months ended June 30, 2016. This correction is immaterial to our financial statements and corresponding disclosures. Our second quarter 2017 interim condensed consolidated financial statements reflect this determination within the calculation of basic and diluted weighted average shares outstanding and earnings per share for the three and six months ended June 30, 2017 and 2016. We assessed the materiality of these changes on our 2016 financial statements in accordance with SEC Staff Accounting Bulletin ("SAB") No. 99, Materiality, codified in Accounting Standards Codification ("ASC") 250, Presentation of Financial Statements, and concluded that they were not material to any prior annual or interim periods. We have corrected the second quarter 2016 by revising the second quarter 2016 interim condensed consolidated financial statements and other financial information included herein. Future periods will be revised, as applicable. The components of basic and diluted net income per common share were as follows for the periods stated: For the Three Months Ended June 30, For the Six Months Ended June 30, (in thousands, except for share and per share amounts) 2017 2016 2017 2016 Numerator: Net income $ 1,498 $ 3,451 $ 2,352 $ 6,895 Denominator: Weighted average shares used to compute net income per common share - basic 20,353,801 20,568,058 20,441,781 20,637,070 Weighted average shares used to compute net income per common share - diluted 20,366,102 20,568,058 20,508,473 20,637,070 Basic net income per common share $ 0.07 $ 0.17 $ 0.12 $ 0.33 Diluted net income per common share $ 0.07 $ 0.17 $ 0.11 $ 0.33 Spok Holdings, Inc. Equity Incentive Award Plan The following table summarizes the activities under the 2012 Equity Incentive Award Plan ("2012 Equity Plan") from January 1, 2017 through June 30, 2017 : Activity Total equity securities available at January 1, 2017 1,246,939 Less: 2015 Performance-Based LTIP RSUs awarded to eligible employees, net of forfeitures 112,202 Less: 2017 Time-Based LTIP RSUs awarded to eligible employees, net of forfeitures 117,471 Less: Restricted stock awarded to non-executive members of the Board of Directors 10,047 Total equity securities available at June 30, 2017 1,007,219 On July 24, 2017 the Company's stockholders approved an amendment to our 2012 Equity Plan to: (i) expand the list of performance criteria that may be used for purposes of granting performance awards under the 2012 Equity Plan, and (ii) limit the annual value awards that may be granted to the Company's non-employee directors to $750,000 per year, subject to limited exceptions as described in the amendment. The approval of the amendment was intended to satisfy the stockholder approval requirements under Section 162(m) of the Internal Revenue Code. 2015 Long Term Incentive Plan. On December 9, 2014, our Board of Directors adopted the 2015 LTIP (which provides for a 36 -month vesting period) that included a stock component in the form of RSUs. Under this incentive program, RSUs will be granted to eligible employees annually and each annual grant will generally vest over a three-year service period. Each annual grant includes performance metrics required to be met for vesting purposes, as established by the Board of Directors. Our Board of Directors also approved that future cash dividends related to the RSUs will be set aside and paid in cash to each eligible employee when the RSUs are converted into shares of common stock. RSUs would be converted into shares of common stock on the earlier of a change in control of the Company (as defined in the 2015 LTIP) or on or after the third business day following the day that we file the Annual Report on Form 10-K with the SEC for the grant's final vesting year, but in no event later than December 31 of the year following the vesting date if the pre-established performance conditions are achieved. Any unvested RSUs awarded under the 2015 LTIP and the related cash dividends are forfeited if the participant terminates employment with the Company. On January 2, 2015, our Board of Directors granted 254,777 RSUs with a grant date fair value of $4.4 million . An additional 6,123 RSUs were granted to eligible employees who were promoted or joined the Company during the twelve months ended December 31, 2015. On January 28, 2016, our Board of Directors issued a second grant of 227,082 RSUs with a grant date fair value of $3.8 million . An additional 7,629 RSUs were granted to eligible employees who were promoted or joined the Company during the twelve months ended December 31, 2016. On January 2, 2017, our Board of Directors issued a third grant of 108,428 RSUs with a grant date fair value of $2.2 million . An additional 10,039 RSUs were issued to eligible employees who were promoted or joined the Company during the six months ended June 30, 2017 . All issuances were made to eligible employees under the 2012 Equity Plan for the 2015 LTIP pursuant to a Restricted Stock Unit Agreement. Eligible employees have the opportunity to earn RSUs based upon continued employment with the Company and the achievement of performance goals established by our Board of Directors for our consolidated revenue and operating cash flows (as defined by the Company) during the period of January 1, 2015 through December 31, 2017 (“the 2015-2017 performance period”) for the 2015 grant, the period of January 1, 2016 through December 31, 2018 ("the 2016-2018 performance period") for the 2016 grant, and January 1, 2017 through December 31, 2019 ("the 2017-2019 performance period") for the 2017 grant, respectively. (For additional details regarding stock compensation refer to Note 9 , "Stock Based Compensation".) The following table details activities with respect to RSUs issued and outstanding under the 2015 LTIP for the six months ended June 30, 2017 : Shares Weighted- Total Unrecognized Compensation Cost Weighted-Average Non-vested RSUs at January 1, 2017 451,493 $ 17.10 Granted 118,467 20.52 Vested — — Forfeited (6,265 ) 17.52 Non-vested RSUs at June 30, 2017 563,695 $ 17.81 $ 3,264 18 2017 Time Based Long Term Incentive Plan. On January 2, 2017, our Board of Directors granted 108,394 RSUs with a grant date fair value of $2.2 million . An additional 10,039 shares were issued to eligible employees who were promoted or joined the Company during the six months ended June 30, 2017 . Our Board of Directors also approved that future cash dividends related to the RSUs will be set aside and paid in cash to each eligible employee when the RSUs are converted into shares of common stock. These RSUs vest one third on December 31, 2017, December 31, 2018 and December 31, 2019. RSUs would be converted into shares of common stock on the earlier of a change in control of the Company (as defined in the 2012 Equity Plan) or on or after the third business day following the day that we file the Annual Report on Form 10-K with the SEC for the grant's vesting years, but in no event later than December 31 of the year following the vesting date. Any unvested RSUs awarded under the 2017 time based grant and the related cash dividends are forfeited if the participant terminates employment with the Company. (For additional details regarding stock compensation refer to Note 9 , "Stock Based Compensation".) The following table details activities with respect to RSUs issued and outstanding under the 2017 time based LTIP grant for the six months ended June 30, 2017 : Shares Weighted- Average Grant Date Fair Value Total Unrecognized Compensation Cost Weighted-Average Period Over Which Cost is Expected to be Recognized (In months) Non-vested RSUs at January 1, 2017 — $ — Granted 118,433 20.52 Vested — — Forfeited (962 ) 20.75 Non-vested RSUs at June 30, 2017 117,471 $ 20.52 $ 1,696 18 Employee Stock Purchase Plan. On July 25, 2016, our stockholders approved the registration with the SEC of 250,000 shares of common stock, to be issued from time to time in connection with purchases under the Spok Holdings, Inc. 2016 Employee Stock Purchase Plan ("ESPP"). Shares were first offered for purchase under the ESPP during the third quarter of 2016. Under the ESPP, eligible participants can voluntarily elect to have contributions withheld from their pay for the duration of an offering period, subject to the ESPP limits. At the end of an offering period, contributions will be used to purchase the Company's common stock at a discount to the market price based on the first or last day of the offering period, whichever is lower. Participants are required to hold common stock for a minimum period of two years from the grant date. Participants will begin earning dividends on shares after the purchase date. Each offering period will generally last for no longer than six months. Once an offering period begins, participants cannot adjust their withholding amount. If a participant chooses to withdraw, any previously withheld funds will be returned to the participant, with no stock purchased, and that participant will be eligible to participate in the ESPP at the next offering period. If the participant terminates employment with the Company during the offering period, all contributions will be returned to the employee and no stock will be purchased at a discounted rate. For the three and six months ended June 30, 2017 , 8,983 shares of common stock were purchased for a total cost of $0.1 million . No shares were purchased during the corresponding time periods in 2016. The following table summarizes the activities under the ESPP from January 1, 2017 through June 30, 2017 : Activity Total ESPP equity securities available at January 1, 2017 246,039 Less: ESPP common stock purchased by eligible employees 8,983 Total ESPP securities available at June 30, 2017 237,056 Amounts withheld from participants will be classified as a liability on the balance sheet until funds are used to purchase shares. This liability amount is immaterial to the overall financial statements. (For additional details regarding stock compensation refer to Note 9 , "Stock Based Compensation".)

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Income Taxes	INCOME TAXES Spok files a consolidated U.S. Federal income tax return and income tax returns in various state, local and foreign jurisdictions as required. At June 30, 2017, we had total deferred income tax assets ("DTAs") of $72.0 million and no valuation allowance. This reflects a change from the December 31, 2016 balance of DTAs of $73.1 million and no valuation allowance. The change from December 31, 2016 to June 30, 2017 reflects the expected usage of the DTAs to offset expected 2017 taxable income and changes in tax rates. We consider both positive and negative evidence when evaluating the recoverability of our DTAs. The assessment is required to determine whether based on all available evidence, it is more likely than not (i.e., greater than a 50% probability) whether all or some portion of the DTAs will be realized in the future. During the fourth quarter of each year, we update our multi-year forecast of taxable income for our operations which assists in analyzing the recoverability of our DTAs. The anticipated effective income tax rate is expected to continue to differ from the Federal statutory rate of 35% primarily due to the effect of state income taxes, the effect of changes to the DTA valuation allowance, permanent differences between book and taxable income and certain discrete items. As of January 1, 2017, we had approximately $126 million of Federal Net Operating Losses ("NOLs") available to offset future taxable income.

Stock Based Compensation

Stock Based Compensation	6 Months Ended
	Jun. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Based Compensation	STOCK BASED COMPENSATION We record all stock-based awards, which consist of RSUs, restricted stock and the option to purchase common stock under the ESPP, at fair value as of the grant date. Stock based compensation expense is recognized based on a straight-line amortization basis over the respective service period. Forfeitures and withdrawals are accounted for on an as incurred basis. The following table reflects the items for stock based compensation expense on the condensed consolidated statements of income for the periods stated: For the Three Months Ended June 30, For the Six Months Ended June 30, (Dollars in thousands) 2017 2016 2017 2016 2015 LTIP (performance-based) $ 508 $ 622 $ 998 $ 1,153 2017 LTIP (time-based) 371 — 714 — ESPP 15 — 30 — Board of Directors restricted stock 104 108 211 215 Total stock based compensation expense $ 998 $ 730 $ 1,953 $ 1,368 In the fourth quarter of 2016 we determined that only 50% of the 2015 and 2016 grants made under the 2015 LTIP were expected to vest based on the related performance criteria and our assessment of the anticipated future performance applied to the performance criteria. As such, expenses listed in the table above reflect only the portion of grants and related expense that we anticipate will vest for those awards.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES There have been no material changes during the six months ended June 30, 2017 to the commitments and contingencies previously reported in the 2016 Annual Report.

Related Parties

Related Parties	6 Months Ended
	Jun. 30, 2017
Related Party Transactions [Abstract]
Related Parties	RELATED PARTIES A member of our Board of Directors also serves as a director for an entity that leases transmission tower sites to the Company. For the three months ended June 30, 2017 and 2016 , we incurred site rent expenses of $1.0 million and for the six months ended June 30, 2017 and 2016 , we incurred site rent expenses of $2.0 million from the entity on which the individual serves as a director. Site rent expenses are included in service, rental and maintenance expenses.

Organization and Significant 16

Organization and Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying condensed consolidated financial statements include our accounts and the accounts of our wholly-owned direct and indirect subsidiaries. All significant intercompany accounts and transactions have been eliminated in consolidation. Our condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) and the rules and regulations of the United States Securities and Exchange Commission (the “SEC”). In management's opinion, the unaudited condensed consolidated financial statements include all adjustments and accruals that are necessary for a fair presentation of the results of all interim periods reported herein and all such adjustments are of a normal, recurring nature. Amounts shown on the condensed consolidated statements of income within the operating expense categories of cost of revenue; research and development; service, rental and maintenance; selling and marketing; and general and administrative are recorded exclusive of depreciation, amortization and accretion. These items are shown separately on the condensed consolidated statements of income within operating expenses. Foreign currency translation adjustments were immaterial and are not presented separately in our condensed consolidated financial statements and consequently no statements of comprehensive income are presented. Certain prior period amounts in the condensed consolidated financial statements have been reclassified to conform to the current period's presentation. These reclassifications had no effect on the reported results of operations. In the fourth quarter 2016, the Company concluded that it was appropriate to separately state those operating expenses related to research and development. Previously those expenses had been classified under the Service, Rental and Maintenance operating category. Corresponding reclassifications were made to the condensed consolidated statements of income for the three and six months ended June 30, 2016 . This change in classification has no effect on the previously reported condensed consolidated statements of income for any period. The financial information included herein, other than the condensed consolidated balance sheet as of December 31, 2016 , is unaudited. The condensed consolidated balance sheet at December 31, 2016 has been derived from, but does not include, all the disclosures contained in the audited consolidated financial statements as of and for the year ended December 31, 2016 . These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and accompanying notes included in the Company's Annual Report on Form 10-K for the year ended December 31, 2016 (the “ 2016 Annual Report”). The condensed consolidated statements of income for the interim periods presented are not necessarily indicative of the results that may be expected for a full year.
Use of Estimates	Use of Estimates The preparation of these condensed consolidated financial statements requires management to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues, expenses and related disclosures. On an on-going basis, we evaluate estimates and assumptions, including but not limited to those related to the impairment of long-lived assets, intangible assets subject to amortization and goodwill, accounts receivable allowances, revenue recognition, depreciation expense, asset retirement obligations, severance and income taxes. We base our estimates on historical experience and various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.

Consolidated Financial Statem17

Consolidated Financial Statement Components (Tables)	6 Months Ended
	Jun. 30, 2017
Supplemental Financial Statement Components [Abstract]
Prepaid Expenses and Other	Prepaid expenses and other consisted of the following as of the date stated: (Dollars in thousands) June 30, 2017 December 31, 2016 Prepaid repairs and maintenance $ 2,312 $ 1,561 Prepaid rent 1,559 208 Prepaid commissions 1,469 594 Prepaid taxes 792 100 Other prepaid expenses 1,537 1,921 Total prepaid expenses and other $ 7,669 $ 4,384
Summary of Depreciation, Amortization and Accretion	Depreciation, amortization and accretion expenses consisted of the following for the periods stated: For the Three Months Ended June 30, For the Six Months Ended June 30, (Dollars in thousands) 2017 2016 2017 2016 Depreciation Leasehold improvements $ 75 $ 52 $ 125 $ 98 Asset retirement costs (97 ) (69 ) (195 ) (140 ) Paging and computer equipment 2,028 1,992 4,087 3,995 Furniture, fixtures and vehicles 76 69 141 148 Total depreciation 2,082 2,044 4,158 4,101 Amortization 629 1,035 1,636 2,146 Accretion 140 156 280 311 Total depreciation, amortization and accretion expense $ 2,851 $ 3,235 $ 6,074 $ 6,558
Property, Plant and Equipment	Property and equipment, net consisted of the following as of the date stated: (Dollars in thousands) Useful Life June 30, 2017 December 31, 2016 Leasehold improvements lease term $ 4,051 $ 3,843 Asset retirement costs 1-5 3,289 3,263 Paging and computer equipment 1-5 112,800 113,175 Furniture, fixtures and vehicles 3-5 4,447 2,852 Total property and equipment 124,587 123,133 Accumulated depreciation (110,698 ) (110,315 ) Total property and equipment, net $ 13,889 $ 12,818
Components of Other Current Liabilities	Other current liabilities consisted of the following as of the date stated: (Dollars in thousands) June 30, 2017 December 31, 2016 Accrued outside services $ 1,057 $ 975 Accrued accounting and legal 678 467 Accrued network costs 644 773 Deferred rent and other 255 433 Asset retirement obligations 186 85 Total other current liabilities $ 2,820 $ 2,733
Summary of Other Non-Current Liabilities	Other non-current liabilities consisted of the following as of the date stated: (Dollars in thousands) June 30, 2017 December 31, 2016 Asset retirement obligations $ 7,548 $ 7,472 Deferred rent and other 893 942 Dividends payable 129 507 Total other non-current liabilities $ 8,570 $ 8,921

Intangible Assets, Net (Tables)

Intangible Assets, Net (Tables)	6 Months Ended
	Jun. 30, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Net Consolidated Balance of Amortizable Intangible Assets	The net consolidated balance of intangible assets consisted of the following at June 30, 2017 : June 30, 2017 (Dollars in thousands) Useful Life Gross Carrying Accumulated Net Balance Customer relationships 10 $ 25,002 $ (15,836 ) $ 9,166 Total amortizable intangible assets 10 $ 25,002 $ (15,836 ) $ 9,166
Estimated Amortization of Intangible Assets	Estimated amortization of intangible assets for future periods was as follows: (Dollars in thousands) For the remaining six months ending December 31, 2017 $ 1,250 For the year ending December 31: 2018 2,500 2019 2,500 2020 2,500 2021 416 Total amortizable intangible assets $ 9,166

Asset Retirement Obligations (T

Asset Retirement Obligations (Tables)	6 Months Ended
	Jun. 30, 2017
Asset Retirement Obligation Disclosure [Abstract]
Changes in Asset Retirement Obligation Liabilities	The components of the changes in the asset retirement obligation liabilities were: (Dollars in thousands) Short-Term Long-Term Total Balance at January 1, 2017 $ 85 $ 7,472 $ 7,557 Accretion 4 276 280 Amounts paid (129 ) — (129 ) Asset additions recorded, net — 26 26 Reclassifications 226 (226 ) — Balance at June 30, 2017 $ 186 $ 7,548 $ 7,734

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	6 Months Ended
	Jun. 30, 2017
Equity [Abstract]
Changes in Stockholders' Equity	Changes in stockholders’ equity for the six months ended June 30, 2017 consisted of the following: (Dollars in thousands) Balance at January 1, 2017 $ 322,087 Net income for the six months ended June 30, 2017 2,352 Cash dividends declared (5,221 ) Common stock repurchase program (10,024 ) Amortization of stock based compensation 1,953 Other 363 Balance at June 30, 2017 $ 311,510
Cash Dividends Declared	The following table details our cash dividend payments made in 2017 . Cash dividends paid as disclosed in the condensed consolidated statements of cash flows for the six months ended June 30, 2017 and 2016 include previously declared cash dividends on shares of vested restricted common stock ("restricted stock") issued to our non-executive directors and dividends related to vested restricted stock units ("RSUs") issued to eligible employees. Cash dividends on RSUs and restricted stock have been accrued and are paid when the applicable vesting conditions are met. Accrued cash dividends on forfeited restricted stock and RSUs are also forfeited. Declaration Date Record Date Payment Date Per Share Amount Total Payment (1) (Dollars in thousands) December 20, 2016 January 4, 2017 January 17, 2017 $ 0.250 $ 5,128 March 1, 2017 March 17, 2017 March 30, 2017 0.125 2,566 April 26, 2017 May 23, 2017 June 23, 2017 0.125 2,545 Total $ 0.500 $ 10,239 (1) The total payment reflects the cash dividends paid in relation to common stock and vested restricted stock.
Share Repurchase Plan	The following table presents information with respect to purchases made by the Company during the six months ended June 30, 2017 : Period Total Number of Shares Purchased Average Price Paid Per Share Total Number of Shares Purchased as Part of the Publicly Announced Plans or Programs Approximate Dollar Value of Shares That May Yet Be Purchased Under the Publicly Announced Plans or Programs (Dollars in thousands) Beginning Balance $ 10,000 Three Months Ended June 30, 2017 572,550 17.47 572,550 — Total 572,550 $ 17.47 572,550
Basic and Diluted Net Income Per Common Shares	The components of basic and diluted net income per common share were as follows for the periods stated: For the Three Months Ended June 30, For the Six Months Ended June 30, (in thousands, except for share and per share amounts) 2017 2016 2017 2016 Numerator: Net income $ 1,498 $ 3,451 $ 2,352 $ 6,895 Denominator: Weighted average shares used to compute net income per common share - basic 20,353,801 20,568,058 20,441,781 20,637,070 Weighted average shares used to compute net income per common share - diluted 20,366,102 20,568,058 20,508,473 20,637,070 Basic net income per common share $ 0.07 $ 0.17 $ 0.12 $ 0.33 Diluted net income per common share $ 0.07 $ 0.17 $ 0.11 $ 0.33
Summary of Outstanding RSUs under 2011 LTIP	The following table details activities with respect to RSUs issued and outstanding under the 2017 time based LTIP grant for the six months ended June 30, 2017 : Shares Weighted- Average Grant Date Fair Value Total Unrecognized Compensation Cost Weighted-Average Period Over Which Cost is Expected to be Recognized (In months) Non-vested RSUs at January 1, 2017 — $ — Granted 118,433 20.52 Vested — — Forfeited (962 ) 20.75 Non-vested RSUs at June 30, 2017 117,471 $ 20.52 $ 1,696 18 The following table details activities with respect to RSUs issued and outstanding under the 2015 LTIP for the six months ended June 30, 2017 : Shares Weighted- Total Unrecognized Compensation Cost Weighted-Average Non-vested RSUs at January 1, 2017 451,493 $ 17.10 Granted 118,467 20.52 Vested — — Forfeited (6,265 ) 17.52 Non-vested RSUs at June 30, 2017 563,695 $ 17.81 $ 3,264 18
Activities Under Equity Plan	The following table summarizes the activities under the 2012 Equity Incentive Award Plan ("2012 Equity Plan") from January 1, 2017 through June 30, 2017 : Activity Total equity securities available at January 1, 2017 1,246,939 Less: 2015 Performance-Based LTIP RSUs awarded to eligible employees, net of forfeitures 112,202 Less: 2017 Time-Based LTIP RSUs awarded to eligible employees, net of forfeitures 117,471 Less: Restricted stock awarded to non-executive members of the Board of Directors 10,047 Total equity securities available at June 30, 2017 1,007,219 For the three and six months ended June 30, 2017 , 8,983 shares of common stock were purchased for a total cost of $0.1 million . No shares were purchased during the corresponding time periods in 2016. The following table summarizes the activities under the ESPP from January 1, 2017 through June 30, 2017 : Activity Total ESPP equity securities available at January 1, 2017 246,039 Less: ESPP common stock purchased by eligible employees 8,983 Total ESPP securities available at June 30, 2017 237,056

Stock Based Compensation (Table

Stock Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Based Compensation Expense	The following table reflects the items for stock based compensation expense on the condensed consolidated statements of income for the periods stated: For the Three Months Ended June 30, For the Six Months Ended June 30, (Dollars in thousands) 2017 2016 2017 2016 2015 LTIP (performance-based) $ 508 $ 622 $ 998 $ 1,153 2017 LTIP (time-based) 371 — 714 — ESPP 15 — 30 — Board of Directors restricted stock 104 108 211 215 Total stock based compensation expense $ 998 $ 730 $ 1,953 $ 1,368

Organization and Significant 22

Organization and Significant Accounting Policies (Details)	6 Months Ended
	Jun. 30, 2017message
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Monthly messages sent through company solutions (over 100 million)	100,000,000

Consolidated Financial Statem23

Consolidated Financial Statement Components - Prepaid Expenses and Other (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid repairs and maintenance	$ 2,312	$ 1,561
Prepaid rent	1,559	208
Prepaid commissions	1,469	594
Prepaid taxes	792	100
Prepaid expenses	1,537	1,921
Total prepaid expenses and other	$ 7,669	$ 4,384

Consolidated Financial Statem24

Consolidated Financial Statement Components - Depreciation, Amortization and Accretion (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Property, Plant and Equipment [Line Items]
Depreciation	$ 2,082	$ 2,044	$ 4,158	$ 4,101
Amortization	629	1,035	1,636	2,146
Accretion	140	156	280	311
Total depreciation, amortization and accretion expense	2,851	3,235	6,074	6,558
Leasehold improvements
Property, Plant and Equipment [Line Items]
Depreciation	75	52	125	98
Asset retirement costs
Property, Plant and Equipment [Line Items]
Depreciation	(97)	(69)	(195)	(140)
Paging and computer equipment
Property, Plant and Equipment [Line Items]
Depreciation	2,028	1,992	4,087	3,995
Furniture, fixtures and vehicles
Property, Plant and Equipment [Line Items]
Depreciation	$ 76	$ 69	$ 141	$ 148

Consolidated Financial Statem25

Consolidated Financial Statement Components - Property and Equipment, Net (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Accounts receivable allowance	$ 1,100	$ 1,100
Total property and equipment	124,587	123,133
Accumulated depreciation	(110,698)	(110,315)
Total property and equipment, net	13,889	12,818
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	4,051	3,843
Asset retirement costs
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 3,289	3,263
Asset retirement costs | Minimum
Property, Plant and Equipment [Line Items]
Useful Life	1 year
Asset retirement costs | Maximum
Property, Plant and Equipment [Line Items]
Useful Life	5 years
Paging and computer equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 112,800	113,175
Paging and computer equipment | Minimum
Property, Plant and Equipment [Line Items]
Useful Life	1 year
Paging and computer equipment | Maximum
Property, Plant and Equipment [Line Items]
Useful Life	5 years
Furniture, fixtures and vehicles
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 4,447	$ 2,852
Furniture, fixtures and vehicles | Minimum
Property, Plant and Equipment [Line Items]
Useful Life	3 years
Furniture, fixtures and vehicles | Maximum
Property, Plant and Equipment [Line Items]
Useful Life	5 years

Consolidated Financial Statem26

Consolidated Financial Statement Components - Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Supplemental Balance Sheet Information [Abstract]
Accrued outside services	$ 1,057	$ 975
Accrued accounting and legal	678	467
Accrued network costs	644	773
Deferred rent and other	255	433
Asset retirement obligations	186	85
Total other current liabilities	$ 2,820	$ 2,733

Consolidated Financial Statem27

Consolidated Financial Statement Components - Other Non-current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Supplemental Balance Sheet Information [Abstract]
Asset retirement obligations	$ 7,548	$ 7,472
Deferred rent and other	893	942
Dividends payable	129	507
Total other long-term liabilities	$ 8,570	$ 8,921

Intangible Assets, Net - Additi

Intangible Assets, Net - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Useful Life (In Years)	10 years

Intangible Assets, Net - Net Co

Intangible Assets, Net - Net Consolidated Balance of Amortizable Intangible Assets (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	10 years
Gross Carrying Amount	$ 25,002
Accumulated Amortization	(15,836)
Total amortizable intangible assets	$ 9,166	$ 10,803
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Useful Life (In Years)	10 years
Gross Carrying Amount	$ 25,002
Accumulated Amortization	(15,836)
Total amortizable intangible assets	$ 9,166

Intangible Assets, Net - Estima

Intangible Assets, Net - Estimated Amortization of Intangible Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
For the remaining six months ending December 31, 2017	$ 1,250
2,018	2,500
2,019	2,500
2,020	2,500
2,021	416
Total amortizable intangible assets	$ 9,166	$ 10,803

Asset Retirement Obligations -

Asset Retirement Obligations - Changes in Asset Retirement Obligation Liabilities (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at January 1, 2017			$ 7,557
Accretion	$ 140	$ 156	280	$ 311
Amounts paid			(129)
Asset additions recorded, net			26
Reclassifications			0
Balance at June 30, 2017	7,734		7,734
Short-Term Portion
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at January 1, 2017			85
Accretion			4
Amounts paid			(129)
Asset additions recorded, net			0
Reclassifications			226
Balance at June 30, 2017	186		186
Long-Term Portion
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Balance at January 1, 2017			7,472
Accretion			276
Amounts paid			0
Asset additions recorded, net			26
Reclassifications			(226)
Balance at June 30, 2017	$ 7,548		$ 7,548

Asset Retirement Obligations 32

Asset Retirement Obligations - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Asset Retirement Obligation Disclosure [Abstract]
Estimated liability	$ 9,000		$ 9,000
Accretion	$ 140	$ 156	$ 280	$ 311

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($)

Jan. 02, 2017

Jan. 28, 2016

Jan. 02, 2015

Dec. 09, 2014

Jun. 30, 2017

Jun. 30, 2017

Jun. 30, 2016

Jun. 30, 2017

Jun. 30, 2016

Dec. 31, 2016

Dec. 31, 2015

Jul. 26, 2017

Jul. 24, 2017

Apr. 26, 2017

Jul. 25, 2016

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Common stock authorized (shares)

75,000,000

75,000,000

75,000,000

Common stock par value (usd per share)

$ 0.0001

$ 0.0001

$ 0.0001

Preferred stock authorized (shares)

25,000,000

25,000,000

25,000,000

Preferred stock par value (usd per share)

$ 0.0001

$ 0.0001

$ 0.0001

Options outstanding (shares)

0

0

0

0

Common stock outstanding (shares)

19,972,094

19,972,094

19,972,094

20,525,614

Preferred stock outstanding (shares)

0

0

0

0

Stock repurchase authority

$ 10,000,000

Amount spent to repurchase common stock

$ 10,000,000

$ 10,024,000

ESPP

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Less: stock purchased by eligible employees, net of forfeitures (shares)

8,983

0

8,983

0

Proceeds from issuance of common stock

$ 100,000

$ 100,000

Number of shares authorized (shares)

246,039

250,000

Award required holding period

2 years

2015 LTIP (performance-based) | Restricted Stock Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Vesting period

36 months

Granted (shares)

118,467

2012 Equity Plan

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Number of shares authorized (shares)

1,246,939

2012 Equity Plan | Restricted Stock Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Granted (shares)

117,471

2017 LTIP (time-based) | Restricted Stock Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Granted (shares)

118,433

January 2, 2015 | 2015 LTIP (performance-based) | Restricted Stock Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Granted (shares)

254,777

Granted

$ 4,400,000

January 28, 2016 | 2015 LTIP (performance-based) | Restricted Stock Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Granted (shares)

227,082

Granted

$ 3,800,000

January 2, 2017 | 2015 LTIP (performance-based) | Restricted Stock Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Granted (shares)

108,428

Granted

$ 2,200,000

January 2, 2017 | 2017 LTIP (time-based) | Restricted Stock Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Granted (shares)

108,394

Granted

$ 2,200,000

Award vesting percentage

33.00%

New Employees or Promoted Employees | 2015 LTIP (performance-based) | Restricted Stock Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Granted (shares)

7,629

New Employees or Promoted Employees | January 2, 2015 | 2015 LTIP (performance-based) | Restricted Stock Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Granted (shares)

6,123

New Employees or Promoted Employees | January 2, 2017 | 2015 LTIP (performance-based) | Restricted Stock Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Granted (shares)

10,039

New Employees or Promoted Employees | January 2, 2017 | 2017 LTIP (time-based) | Restricted Stock Units

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Granted (shares)

10,039

Maximum | ESPP

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Offering period, maximum

6 months

Subsequent Event

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Dividend rate (usd per share)

$ 0.125

Dividends declared

$ 2,500,000

Subsequent Event | Non-Employee Directors | 2012 Equity Plan

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Annual limit to the value of awards granted

$ 750,000

Stockholders' Equity - Changes

Stockholders' Equity - Changes in Stockholders' Equity (Detail) - USD ($) $ in Thousands	2 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at January 1, 2017				$ 322,087
Net income for the six months ended June 30, 2017		$ 1,498	$ 3,451	2,352	$ 6,895
Cash dividends declared				(5,221)
Common stock repurchase program	$ (10,000)			(10,024)
Amortization of stock based compensation				1,953
Other				363
Balance at June 30, 2017	$ 311,510	$ 311,510		$ 311,510

Stockholders' Equity - Cash Div

Stockholders' Equity - Cash Dividends Declared to Stockholders (Detail) - Common Stock $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2017USD ($)$ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Per Share Amount (usd per share) | $ / shares	$ 0.5
Total Payment | $	$ 10,239
Installment One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Declaration Date	Dec. 20, 2016
Record Date	Jan. 4, 2017
Payment Date	Jan. 17, 2017
Per Share Amount (usd per share) | $ / shares	$ 0.25
Total Payment | $	$ 5,128
Installment Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Declaration Date	Mar. 1, 2017
Record Date	Mar. 17, 2017
Payment Date	Mar. 30, 2017
Per Share Amount (usd per share) | $ / shares	$ 0.125
Total Payment | $	$ 2,566
Installment Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Declaration Date	Apr. 26, 2017
Record Date	May 23, 2017
Payment Date	Jun. 23, 2017
Per Share Amount (usd per share) | $ / shares	$ 0.125
Total Payment | $	$ 2,545

Stockholders' Equity - Treasury

Stockholders' Equity - Treasury Stock (Details) - USD ($)	6 Months Ended
	Jun. 30, 2017	Apr. 26, 2017	Dec. 31, 2016
Equity, Class of Treasury Stock [Line Items]
Stock repurchase authority		$ 10,000,000
Total Number of Shares Purchased
Total number of shares purchased (shares)
Shares purchased during period (shares)	572,550
Total number of shares purchased (shares)	572,550
Average price paid per share, beginning balance (usd per share)
Average price paid per share (usd per share)	17.47
Average price paid per share, ending balance (usd per share)	$ 17.47
Approximate dollar value of shares that may yet be purchased under the publicly announced plans or programs			$ 10,000,000
Common Stock Repurchase Program
Total Number of Shares Purchased
Total number of shares purchased (shares)
Shares purchased during period (shares)	572,550
Total number of shares purchased (shares)	572,550

Stockholders' Equity - Basic an

Stockholders' Equity - Basic and Diluted Net Income Per Common Shares (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Numerator:
Net income	$ 1,498	$ 3,451	$ 2,352	$ 6,895
Denominator:
Weighted average shares used to compute net income per common share - basic (shares)	20,353,801	20,568,058	20,441,781	20,637,070
Weighted average shares used to compute net income per common share - diluted (shares)	20,366,102	20,568,058	20,508,473	20,637,070
Basic net income per common share (usd per share)	$ 0.07	$ 0.17	$ 0.12	$ 0.33
Diluted net income per common share (usd per share)	$ 0.07	$ 0.17	$ 0.11	$ 0.33

Stockholders' Equity - Activiti

Stockholders' Equity - Activities Under Equity Plan (Detail) - shares	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016	Jul. 25, 2016
2012 Equity Plan
Share-based Compensation Arrangement By Share-based Payment Award, Shares Authorized [Roll Forward]
Total equity securities available at January 1, 2017 (shares)		1,246,939
Total equity securities available at March 31, 2017 (shares)	1,007,219
ESPP
Share-based Compensation Arrangement By Share-based Payment Award, Shares Authorized [Roll Forward]
Total equity securities available at January 1, 2017 (shares)		246,039	250,000
Total equity securities available at March 31, 2017 (shares)	237,056
Restricted Stock Units | 2012 Equity Plan
Share-based Compensation Arrangement By Share-based Payment Award, Shares Authorized [Roll Forward]
Less: Restricted stock awarded to non-executive members of the Board of Directors (shares)	117,471
Eligible Employees | Restricted Stock Units | 2012 Equity Plan
Share-based Compensation Arrangement By Share-based Payment Award, Shares Authorized [Roll Forward]
Less: Restricted stock awarded to non-executive members of the Board of Directors (shares)	112,202
Board Of Directors | Restricted Stock | 2012 Equity Plan
Share-based Compensation Arrangement By Share-based Payment Award, Shares Authorized [Roll Forward]
Less: Restricted stock awarded to non-executive members of the Board of Directors (shares)	10,047

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Outstanding RSUs (Detail) - Restricted Stock Units $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2017USD ($)$ / sharesshares
2015 LTIP (performance-based)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Beginning Balance (shares) | shares	451,493
Granted (shares) | shares	118,467
Vested (shares) | shares	0
Forfeited (shares) | shares	(6,265)
Ending Balance (shares) | shares	563,695
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Beginning Balance, Weighted Average Grant Date Fair Value (usd per share) | $ / shares	$ 17.10
Granted, Weighted Average Grant Date Fair Value (usd per share) | $ / shares	20.52
Vested, Weighted Average Grant Date Fair Value (usd per share) | $ / shares	0
Forfeited, Weighted Average Grant Date Fair Value (usd per share) | $ / shares	17.52
Ending Balance, Weighted Average Grant Date Fair Value (usd per share) | $ / shares	$ 17.81
Total Unrecognized Compensation Cost (net of estimated forfeitures) | $	$ 3,264
Weighted-Average Period Over Which Cost is Expected to be Recognized	18 months
2017 LTIP (time-based)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Beginning Balance (shares) | shares	0
Granted (shares) | shares	118,433
Vested (shares) | shares	0
Forfeited (shares) | shares	(962)
Ending Balance (shares) | shares	117,471
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Beginning Balance, Weighted Average Grant Date Fair Value (usd per share) | $ / shares	$ 0
Granted, Weighted Average Grant Date Fair Value (usd per share) | $ / shares	20.52
Vested, Weighted Average Grant Date Fair Value (usd per share) | $ / shares	0
Forfeited, Weighted Average Grant Date Fair Value (usd per share) | $ / shares	20.75
Ending Balance, Weighted Average Grant Date Fair Value (usd per share) | $ / shares	$ 20.52
Total Unrecognized Compensation Cost (net of estimated forfeitures) | $	$ 1,696
Weighted-Average Period Over Which Cost is Expected to be Recognized	18 months

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Deferred income tax assets	$ 72,018,000	$ 73,068,000
Valuation allowance	$ 0	0
Percentage of probability of deferred income tax realized in future	50.00%
Valuation allowance, methodologies and assumptions	"more likely than not" (greater than a 50% probability)
Federal income tax at statutory rate	35.00%
Approximate Federal net operating losses (NOLs) available to offset future taxable income		$ 126,000,000

Stock Based Compensation (Detai

Stock Based Compensation (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Share based Compensation Allocation of Recognized Period Cost [Line Items]
Total stock based compensation expense	$ 998	$ 730	$ 1,953	$ 1,368
Expected vesting percent					50.00%
2015 LTIP (performance-based)
Share based Compensation Allocation of Recognized Period Cost [Line Items]
Total stock based compensation expense	508	622	998	1,153
2017 LTIP (time-based)
Share based Compensation Allocation of Recognized Period Cost [Line Items]
Total stock based compensation expense	371	0	714	0
ESPP
Share based Compensation Allocation of Recognized Period Cost [Line Items]
Total stock based compensation expense	15	0	30	0
Board Of Directors | Board of Directors restricted stock | Restricted Stock
Share based Compensation Allocation of Recognized Period Cost [Line Items]
Total stock based compensation expense	$ 104	$ 108	$ 211	$ 215

Related Parties - Additional In

Related Parties - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Director
Related Party Transaction [Line Items]
Site rent expense	$ 1	$ 1	$ 2	$ 2