Navigator (NVGS) 20-F 28 Apr 22 2021 FY Annual report (foreign) Financial data

CoverPage

CoverPage - shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Document Type	20-F
Amendment Flag	false
Document Period End Date	Dec. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Document Registration Statement	false
Document Annual Report	true
Document Transition Report	false
Document Shell Company Report	false
Trading Symbol	NVGS
Security Exchange Name	NYSE
Entity Address, Country	GB
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock
Entity Incorporation, State or Country Code	1T
Entity Registrant Name	NAVIGATOR HOLDINGS LTD.
Entity Central Index Key	0001581804
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Filer Category	Accelerated Filer
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding	77,180,429
Entity Address, Address Line One	10 Bressenden Place
Document Accounting Standard	U.S. GAAP
Entity Address, City or Town	London
Entity Address, Postal Zip Code	SW1E 5DH
Entity File Number	001-36202
ICFR Auditor Attestation Flag	true
Auditor Name	PricewaterhouseCoopers LLP	Ernst & Young LLP	DELOITTE & TOUCHE LLP
Auditor Firm ID	876	1438	34
Auditor Location	Watford, United Kingdom	London United Kingdom	Houston, Texas
Business Contact [Member]
Entity Address, Country	GB
Entity Address, Address Line One	10 Bressenden Place
Entity Address, City or Town	London
Entity Address, Postal Zip Code	SW1E 5DH
Contact Personnel Name	Niall Nolan
City Area Code	20
Local Phone Number	7340 4850

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets
Cash, cash equivalents and restricted cash	$ 124,223	$ 59,271
Accounts receivable, net of allowance for credit losses of $1,105 (December 31, 2020: $161)	31,906	14,451
Accrued income	6,150	20,073
Prepaid expenses and other current assets	16,293	22,015
Bunkers and lubricant oils	13,171	8,428
Insurance receivable	6,857	447
Amounts due from related parties	16,736	11,853
Total current assets	215,336	136,538
Non-current assets
Assets held for sale	25,944
Property, plant and equipment, net	330	502
Intangible assets, net of accumulated amortization of $387 (December 31, 2020: $279)	400	277
Equity method investments	150,209	148,665
Derivative assets	579
Right-of-use asset for operating leases	923	5,701
Prepaid expenses and other non- current assets	452	2,037
Total non-current assets	1,942,089	1,702,870
Total assets	2,157,425	1,839,408
Current liabilities
Current portion of secured term loan facilities, net of deferred financing costs	148,570	65,662
Current portion of operating lease liabilities	381	1,276
Accounts payable	11,600	8,565
Accrued expenses and other liabilities	20,247	16,488
Accrued interest	5,211	3,398
Deferred income	18,510	11,604
Amounts due to related parties	224	229
Total current liabilities	204,743	107,222
Non-current liabilities
Secured term loan facilities and revolving credit facilities, net of current portion and deferred financing costs	604,790	552,595
Senior secured bond, net of deferred financing costs	67,688	69,580
Senior unsecured bond, net of deferred financing costs	98,551	98,158
Derivative liabilities	8,800	3,007
Operating lease liabilities, net of current portion	522	5,232
Amounts due to related parties	54,877	61,219
Total liabilities	835,228	789,791
Total Liabilities	1,039,971	897,013
Commitments and contingencies
Stockholders' equity
Common stock—$0.01 par value per share; 400,000,000 shares authorized; 77,180,429 shares issued and outstanding, (December 31, 2020: 55,893,618)	772	559
Additional paid-in capital	797,324	593,254
Accumulated other comprehensive loss	(253)	(245)
Retained earnings	316,008	346,972
Total Navigator Holdings Ltd. stockholders' equity	1,113,851	940,540
Non-controlling interest	3,603	1,855
Total equity	1,117,454	942,395
Total liabilities and equity	2,157,425	1,839,408
Vessels [Member]
Non-current assets
Property, plant and equipment, net	$ 1,763,252	$ 1,545,688

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Allowanace for doubt debts on accounts receivable current	$ 1,105	$ 161
Intangible assets, Accumulated amortization	$ 387	$ 279
Common stock, par value	$ 0.01	$ 0.01
Common stock, authorized	400,000,000	400,000,000
Common stock, shares issued	77,180,429	55,893,618
Common stock, shares outstanding	77,180,429	55,893,618

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues
Operating revenues	$ 352,922	$ 319,665	$ 301,385
Operating Revenues Unigas Pool	27,004
Operating revenues—Luna Pool collaborative arrangements	26,555	12,830
Total operating revenues	406,481	332,495	301,385
Expenses
Brokerage commissions	4,802	5,095	4,938
Voyage expenses	71,953	63,372	55,310
Voyage expenses—Luna Pool collaborative arrangements	20,913	12,418
Vessel operating expenses	131,183	109,503	111,475
Depreciation and amortization	88,486	76,681	76,173
Vessel impairments	63,581
General and administrative costs	28,881	23,871	20,878
Other income	(367)	(199)
Total operating expenses	409,432	290,741	268,774
Operating income/(loss)	(2,951)	41,754	32,611
Other income/(expense)
Foreign currency exchange gain/(loss) on senior secured bonds	2,146	(1,931)	969
Unrealized (loss)/gain on non-designated derivative instruments	791	2,762	(615)
Interest expense	(38,682)	(41,080)	(48,611)
Loss on repayment of 7.75% senior unsecured bonds		(479)
Write off of deferred financing costs		(155)	(403)
Interest income	302	408	920
(Loss)/income before income taxes and share of equity method investments	(38,394)	1,279	(15,129)
Income taxes	(1,969)	(617)	(352)
Share of equity method investments	11,147	651	(1,126)
Net (loss)/income	(29,216)	1,313	(16,607)
Net income attributable to non-controlling interest	(1,748)	(1,756)	(99)
Net loss attributable to stockholders of Navigator Holdings Ltd.	$ (30,964)	$ (443)	$ (16,706)
Loss per share attributable to stockholders of Navigator Holdings Ltd.:
Basic and diluted:	$ (0.48)	$ (0.01)	$ (0.30)
Weighted average number of shares outstanding:
Basic and diluted	64,669,567	55,885,376	55,792,711

Consolidated Statements of Op_2

Consolidated Statements of Operations (Parenthetical)	Dec. 31, 2021
Interest rate on bond	7.75%

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net (loss)/income	$ (29,216)	$ 1,313	$ (16,607)
Other comprehensive income / (loss):
Foreign currency translation gain/(loss)	(8)	86	32
Total comprehensive (loss)/income	(29,224)	1,399	(16,575)
Total comprehensive (loss)/income attributable to:
Stockholders of Navigator Holdings Ltd:	(30,972)	(357)	(16,674)
Non-controlling interests:	1,748	1,756	99
Total comprehensive (loss)/income	$ (29,224)	$ 1,399	$ (16,575)

Consolidated Statements of Shar

Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Issued March 17, 2021 [Member]	Common Stock [Member]	Common Stock [Member]Issued March 17, 2021 [Member]	Common Stock [Member]Issued October 31, 2021 [Member]	Common Stock [Member]Cancelled April 14, 2020 [Member]	Common Stock [Member]Cancelled October 19, 2020 [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]	Noncontrolling Interest [Member]
Beginning Balance at Dec. 31, 2018	$ 955,110		$ 557					$ 590,508	$ (363)	$ 364,408
Beginning Balance, (in shares) at Dec. 31, 2018			55,657,631
Adjustment to equity for the adoption of the new revenue standard	(136)									(136)
Restricted shares issued, (in shares)			174,438
Restricted shares issued	1		$ 1
Restricted shares cancelled			(5,425)
Net (loss)/income	(16,607)									(16,706)	$ 99
Foreign currency translation	32								32
Share-based compensation plan	1,502							1,502
Ending Balance at Dec. 31, 2019	939,902		$ 558					592,010	(331)	347,566	99
Ending Balance, (in shares) at Dec. 31, 2019			55,826,644
Adjustment to equity for the adoption of the new revenue standard	(151)									(151)
Restricted shares issued, (in shares)			79,172
Restricted shares issued	1		$ 1
Restricted shares cancelled						(2,144)	(10,054)
Net (loss)/income	1,313									(443)	1,756
Foreign currency translation	86								86
Share-based compensation plan	1,244							1,244
Ending Balance at Dec. 31, 2020	$ 942,395		$ 559					593,254	(245)	346,972	1,855
Ending Balance, (in shares) at Dec. 31, 2020	55,893,618		55,893,618
Issuance of common stock	$ 202,910		$ 212					202,698
Issuance of common stock, Shares			21,202,671
Restricted shares issued, (in shares)				85,263
Restricted shares issued		$ 1		$ 1
Restricted shares cancelled					15,000		(16,123)
Net (loss)/income	(29,216)									(30,964)	1,748
Foreign currency translation	(8)								(8)
Share-based compensation plan	1,372							1,372
Ending Balance at Dec. 31, 2021	$ 1,117,454		$ 772					$ 797,324	$ (253)	$ 316,008	$ 3,603
Ending Balance, (in shares) at Dec. 31, 2021	77,180,429		77,180,429

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities
Net (loss)/income	$ (29,216)	$ 1,313	$ (16,607)
Adjustments to reconcile net (loss)/income to net cash provided by operating activities
Unrealized loss/(gain) on non-designated derivative instruments	(791)	(2,762)	615
Depreciation and amortization	88,486	76,681	76,173
Payment of drydocking costs	(19,944)	(10,192)	(11,523)
Amortization of share-based compensation expense	1,373	1,245	1,503
Amortization of deferred financing costs	3,668	4,654	4,618
Share of result of equity method investments	(11,147)	(651)	1,126
Call option premium on redemption of 7.75% unsecured bond		236
Impairment losses on vessels	63,581
Changes in operating assets and liabilities
Accounts receivable	(7,874)	8,860	(6,429)
Insurance claim receivable	(8,007)	(975)	(5,107)
Bunkers and lubricant oils	(2,703)	1,217	(856)
Accrued income, prepaid expenses and other current assets	36,566	(20,771)	(637)
Accounts payable, accrued interest, accrued expenses and other liabilities	3,211	(4,118)	7,554
Amounts due from related parties	(16,412)	(12,075)
Net cash provided by operating activities	97,989	44,673	49,700
Cash flows from investing activities
Additions to vessels and equipment	(3,150)	(2,233)	(2,910)
Contributions to equity method investments	(4,000)	(17,354)	(89,324)
Distributions from equity method investments	16,183
Purchase of other property, plant and equipment and intangibles	(390)	(31)	(357)
Cash acquired with investment in Ultragas	17,477
Net proceeds from sale of vessel	4,530
Insurance recoveries	2,407	3,467	2,182
Net cash (used in)/provided by investing activities	33,057	(16,151)	(90,409)
Cash flows from financing activities
Proceeds from secured term loan facilities and revolving credit facilities	18,000	51,000	162,000
Proceeds from revolving loan facility		185,000
Proceeds from refinancing of vessel to related parties			69,052
Issuance of 8.00% senior unsecured bonds		100,000
Issuance costs of unsecured bond amendment			(1,308)
Issuance cost of refinancing of vessel		(18)	(156)
Direct financing cost of secured term loan and revolving credit facilities	(26)	(1,939)	(1,448)
Direct financing cost of terminal credit facility		(72)	(2,833)
Repayment of secured term loan facilities and revolving credit facilities	(77,726)	(260,167)	(189,001)
Repayment of 7.75% senior unsecured bonds		(100,236)
Repayment of refinancing of vessel to related parties	(6,342)	(6,845)	(846)
Net cash provided by/(used in) financing activities	(66,094)	(35,381)	35,324
Net (decrease)/increase in cash, cash equivalents and restricted cash	64,952	(6,859)	(5,385)
Cash, cash equivalents and restricted cash at beginning of period	59,271	66,130	71,515
Cash, cash equivalents and restricted cash at end of period	124,223	59,271	66,130
Supplemental Information
Total interest paid during the year, net of amounts capitalized	33,023	37,619	44,859
Total tax paid during the year	579	330	323
Senior Secured Bonds [Member]
Adjustments to reconcile net (loss)/income to net cash provided by operating activities
Foreign exchange (gain)/loss on senior secured bonds	(2,146)	1,931	(969)
Cash flows from financing activities
Issuance cost		(141)	(136)
Other [Member]
Adjustments to reconcile net (loss)/income to net cash provided by operating activities
Other unrealized foreign exchange loss/(gain)	(656)	80	$ 239
2017 Senior Unsecured Bonds [Member]
Cash flows from financing activities
Issuance cost		$ (1,963)
Secured Bonds [Member]
Cash flows from financing activities
Issuance cost	$ 0

Consolidated Statements of Ca_2

Consolidated Statements of Cash Flows (Parenthetical)	Dec. 31, 2021	Dec. 31, 2020
Interest rate on bond	7.75%
2017 Senior Unsecured Bonds [Member]
Interest rate on bond	8.00%	8.00%
2012 Senior Unsecured Bonds [Member]
Interest rate on bond	7.75%	7.75%

Description of Business

Description of Business	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Description of Business	1. Description of Business Navigator Holdings Ltd. (the “Company”), the ultimate parent company of the Navigator Group of companies, is registered in the Republic of the Marshall Islands. The Company has a core business of owning and operating a fleet of liquefied gas carriers. As of December 31, 2021, the Company owned and operated 55 gas carriers (the “Vessels”) each having a cargo capacity of between 3,770 cbm and 38,000 cbm, of which 31 were ethylene and ethane capable vessels. The Company owns a 50% share, through a joint venture, of an ethylene Marine Export Terminal at Morgan’s Point in Texas, capable of exporting in excess of one million tons of ethylene per year. Unless the context otherwise requires, all references in the consolidated financial statements to “our”,” we” and “us” refer to the Company. In August 2021, the company acquired the fleet and businesses of two entities, Othello Shipping Company S.A. (Othello Shipping”) and Ultragas ApS (“Ultragas”) from Naviera Ultranav Limitada (“Ultranav” and such acquisition, the “ Ultragas Transaction”).

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies (a) Basis of Presentation The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Management has evaluated the Company’s ability to continue as a going concern and considered the conditions and events that could raise substantial doubt about the Company’s ability to continue as a going concern within 12 months after these financial statements are issued. As part of the assessment, management has considered the following; • the current financial condition and liquidity sources, including current funds available and forecasted future cash flows; • any likely effects of global epidemics or other health crises, such as the recent COVID-19 pandemic; and • the effects of the conflict in Ukraine on the Company’s business, including potential sanctions being imposed on the Company’s customers or on ports to which the Company’s vessels call. Management has determined that it is appropriate to continue to adopt the going concern basis in preparing the financial statements. The accompanying consolidated financial statements include the accounts of the Company and its subsidiaries and Variable Interest Entities (“VIE”) for which the Company is a primary beneficiary are also consolidated (See Note 10—Variable Interest Entities to our consolidated financial statements). All intercompany accounts and transactions have been eliminated in consolidation. On January 31, 2018, the Company announced the execution of definitive agreements creating a 50/50 joint venture with Enterprise Products Partners L.P. (the “Export Terminal Joint Venture”) to construct and operate an ethylene export marine terminal at Morgan’s Point, Texas on the Houston Ship Channel (the “Marine Export Terminal”). Enterprise Products Partners, L.P. is the sole managing member of the Export Terminal Joint Venture and it is also the operator of the Marine Export Terminal. Interests in joint ventures are accounted for using the equity method. They are recognized initially at cost, which includes interest capitalized from the terminal loan facility utilized during the construction phase. The capitalized interest will be amortized over the useful life of the terminal. Subsequent to initial recognition, the consolidated financial statements will include the Company’s share of the profit or loss and other comprehensive income (“OCI”) of equity-accounted investees, until the date on which joint control ceases. The Export Terminal Joint Venture is organized as a limited liability company and maintains separate ownership accounts, consequently we account for our investment using the equity method as our ownership interest is 50% and we exercise joint control over the investee’s operating and financial policies. We disclose our proportionate share of profits and losses from equity method unconsolidated affiliates in the statement of operations and adjust the carrying amount of our equity method investments on the balance sheet accordingly. In March 2020, the Company collaborated with Pacific Gas Pte. Ltd. and Greater Bay Gas Co. Ltd. to form and manage the Luna Pool. We refer to the Company and Greater Bay Gas Co. Ltd. collectively as the “Pool Participants”. As part of the formation of the Luna Pool, a new entity, Luna Pool Agency Limited, (“Pool Agency”) was established in May 2020. The investment in the Pool Agency created a 50/50 joint venture with Greater Bay Gas Co. Ltd. as outlined by Accounting Standards Codification (“ASC”) 323 – Investments -Equity Method and Joint Ventures (“ASC 323”). The Company’s investment in the Pool Agency is accounted for as an equity investment in accordance with the guidance within ASC 810 – Consolidation and ASC 323. Therefore, we account for our investment using the equity method as our ownership interest is 50% and we exercise joint control over the entity’s operating and financial policies. P In August 2021, as part of the Ultragas Transaction Dan-Unity U In August 2021, as part of the Ultragas Transaction P p m The Company has determined that it has a variable interest in UCPI and USPI (each as defined below), and is considered to be the primary beneficiary of each entity as a result of having a controlling financial interest in the entities and has the power to direct the activities that most significantly impact UCPI and USPI’s economic performance. The year ended December 31, 2020 includes an out of period adjustment in the consolidated statements of operations of an additional $0.5 million in general and administrative costs and a decrease of $0.8 million in interest expense, resulting in an overall decrease in the net loss for the year ended December 31, 2020 of $0.3 million, and in the consolidated balance sheets at December 31, 2020, an increase to the investment in the equity accounted joint ventures of $0.3 million. Management believes this out of period adjustment is not material to the annual consolidated financial statements for the year ending December 31, 2020 or any previously issued financial statements. Collaborative arrangements The Pool Participants manage and participate in the activities of the Luna Pool through an executive committee comprising equal membership from both Pool Participants. Certain decisions made by the executive committee as to the operations of the Luna Pool require the unanimous agreement of both participants with others requiring a majority of votes. The Company’s wholly owned subsidiary, NGT Services (UK) Limited acts as commercial manager (“Commercial Manager”) to the Luna Pool. Under the pool agreement, the Commercial Manager is responsible, as agent, for the marketing and chartering of the participating vessels, collection of revenues and paying voyage costs such as port call expenses, bunkers and brokers’ commissions in relation to charter contracts, but the vessel owners continue to be fully responsible for the financing, insurance, crewing and technical management of their respective vessels. The Commercial Manager receives a fee based on the net revenues of the Luna Pool, which is levied on the Pool Participants, which was a net amount of $ 0.4 0.2 Pool revenues and expenses within the Luna Pool are accounted for in accordance with ASC 808 – Collaborative Arrangements; Pool earnings (gross earnings of the pool less costs and overheads of the Luna Pool and fees to the Commercial Manager) are aggregated and then allocated to the Pool Participants in accordance with an apportionment for each participant’s vessels multiplied by the number of days each of their vessels are on hire in the pool during the relevant period and therefore the Company is exposed to risk and rewards dependent on the commercial success of the Luna Pool. We have concluded that the Company is an active participant due to its representation on the executive committee and the participation of the Commercial Manager, as is the other Pool Participant. We have presented our share of net income earned under the Luna Pool collaborative arrangement across a number of lines in our consolidated statements of operations. For revenues and expenses earned/incurred specifically by the Company’s vessels and for which we are deemed to be the principal, these are presented gross on the face of our consolidated statements of operations within operating revenues, voyage expenses and brokerage commissions. Our share of pool net revenues generated by the other Pool Participant’s vessels in the Luna Pool collaborative arrangement is presented on the face of our consolidated statements of operations within operating revenues – Luna Pool collaborative arrangements. The other Pool Participant’s share of pool net revenues generated by our vessels in the pool is presented on the face of our consolidated statements of operations within voyage expenses – Luna Pool collaborative arrangements. The portion of the Commercial Manager’s fee which is due from the other Pool Participant is presented on the face of our consolidated statements of operations as other income. The following table summarizes our net income generated from our participation in the Luna Pool for the years ended December 31, 2020 and 2021. Year ended Year ended (in thousands) Income / (expenses) Time and Voyage Charter Revenues $ 49,613 $ 90,592 Time and Voyage charter revenues from Luna Pool collaborative arrangements 12,830 26,555 Brokerage Commissions (804 ) (1,413 ) Voyage Expenses (14,966 ) (34,130 ) Voyage Expenses – Luna Pool collaborative arrangements (12,418 ) (20,913 ) Total net operating income from the Luna Pool 34,255 60,691 Other Income 199 367 Total net income from the Luna Pool $ 34,454 $ 61,058 (b) Vessels Vessels are stated at cost, which includes the cost of construction, capitalized interest and other direct costs attributable to the construction. The cost of the vessels (excluding the estimated initial drydocking cost is or 2020 (c) Vessels held for sale Assets are classified as held for sale when the Company commits to a plan to sell the asset, the sale is probable within one year, and the asset is available for immediate sale in its present condition. Consideration is given to whether the asset is currently being marketed for sale at a price that is reasonable in relation to its current fair value, and whether actions required to complete the plan indicate that it is unlikely that significant changes to the intention to sell will be made or that the intention to sell will be withdrawn. When assets are classified as held for sale, they are measured at the lower of their carrying amount or fair value less cost to sell and they are tested for impairment. A loss is recognized when the carrying value of the asset exceeds the estimated fair value, less transaction costs. Assets classified as held for sale are no longer depreciated. The net book value one of the vessels held for resale was impaired by $5.4 million as of December 31, 2021. (d) Impairment of Vessels Our vessels are reviewed for impairment when events or circumstances indicate the carrying amount of the vessel may not be recoverable. When such indicators are present, a vessel is tested for recoverability and we recognize an impairment loss if the sum of the future cash flows (undiscounted and excluding interest charges that will be recognized as an expense when incurred) expected to be generated by the vessel over its estimated remaining useful life are less than its carrying value. If we determine that a vessel’s undiscounted cash flows are less than its carrying value, we record an impairment loss equal to the amount by which its carrying amount exceeds its fair value. The new lower cost basis would result in a lower annual depreciation than before the impairment. At December 31, 2021, following a change to the estimated years, there were eight vessels that showed indications of impairment, as their individual carrying values were greater than their respective undiscounted cashflows. By applying a discounted cashflow method to those vessels, we assessed that these vessels be impaired by an aggregate amount of Considerations in making such an impairment evaluation include comparison of current carrying values to anticipated future operating cash flows, expectations with respect to future operations and other relevant factors. The estimates and assumptions regarding expected cash flows require considerable judgment and are based upon historical experience, financial forecasts and industry trends and conditions and reflect management’s assumptions and judgements regarding (i) expected future charter rates; (ii) expected future utilization rates; (iii) the estimated remaining useful lives of the vessels; and (iv) the discount rate applied to the estimated future cash flows. (e) Impairment of Equity Method Investments The equity method investments are reviewed for indicators of impairment when events or circumstances indicate the carrying amount of the investment may not be recoverable. When such indicators are present, we determine if the indicators are ‘other than temporary’ to determine if an impairment exists. If we determine that an impairment exists, a discounted cash flow analysis is carried out based on the future cash flows expected to be generated over the investment’s estimated remaining useful life. The resulting net present value is compared to the carrying value and we would recognize an impairment loss equal to the amount by which the carrying amount exceeds its fair value. (f) Drydocking Costs Each vessel is required to be dry-docked dry-dockings dry-docking. dry-docking dry-docking (g) Intangible assets Intangible assets consist of software acquisition and associated costs of software modification to meet the Company’s internal needs. Intangible assets are amortized on a straight-line basis over the expected life of the software license, product or the expected duration that the software is estimated to contribute to the cash flows of the Company, estimated to be five years. Amortization of intangible assets is included in depreciation and amortization in the Consolidated Statements of Operations. Intangible assets are assessed for impairment when and if impairment indicators exist. An impairment loss is recognized if the carrying amount of an intangible asset is not recoverable and its carrying amount exceeds its fair value. No impairment has been recognized for the years ending December 31, 2021, 2020 and 2019. (h) Cash, Cash Equivalents and Restricted Cash The Company considers highly liquid investments, such as time deposits and certificates of deposit, with an original maturity of three months or less when purchased, to be cash equivalents. As of December 31, 2020, and 2021 and for the years then ended, the Company had balances in U.S. financial institutions in excess of the amounts insured by the Federal Deposit Insurance Corporation (“FDIC”). The Company also maintains cash balances in foreign financial institutions outside of the U.S. which are not covered by the FDIC. Amount s included in restricted cash may represent those required to be set aside as collateral by a contractual agreement with a banking institution for the forecast future liability on the cross-currency interest rate swap agreement at the reporting date, payable on maturity of our 2018 issued senior secured bonds (“2018 Bonds”). If the Norwegian Kroner depreciates relative to the U.S. Dollar beyond a certain threshold, we are required to place cash collateral with our swap providers. As of December 31, 2021, there collateral amount held with the swap provider (December 31, 2020 ). The amounts held as collateral within restricted cash are assessed against daily currency movements and are presented as current assets on the Company’s consolidated balance sheets. (h) Financial Instruments—Debt Securities (i) Accounts Receivable, net The Company carries its accounts receivable at cost less an allowance for expected credit losses. As of December 31, 2021, the Company evaluated its accounts receivable and established an allowance for expected credit losses, based on a history of past write-offs, collections and current credit conditions. As of December 31, 2021, the Company also considers future and reasonable and supportable forecasts of future economic conditions in its allowance for expected credit losses. The Company does not generally charge interest on past-due past-due (j) Bunkers and lubricant oils Bunkers and lubricant oils include bunkers (fuel), for those vessels under voyage charter, and lubricants. Under a time charter, the cost of bunkers is borne by and remains the property of the charterer. Bunkers and lubricant oils are accounted for on a first in, first out basis and are valued at cost. (k) Deferred Finance Costs Costs incurred in connection with obtaining secured term loan facilities, revolving credit facilities and bonds are recorded as deferred financing costs and are amortized to interest expense over the estimated duration of the related debt. Such costs include fees paid to the lenders or on the lenders’ behalf and associated legal and other professional fees. Under the Accounting Standards Update (ASU) 2015- 03, Interest—Imputation of Interest the Company has adopted the accounting standard (Subtopic 835-30)—simplifying (l) Deferred Income Deferred income is the balance of cash received in excess of revenue earned under voyage charter arrangements as of the balance sheet date. Deferred income also includes the unearned portion of time charter revenue invoices for which consideration has not been received as at the balance sheet date, but for which there is an unconditional right to receive such consideration before the performance obligation is satisfied. (m) Accruals and other liabilities Accrued expenses and other liabilities include all accrued liabilities relating to the operations of our vessels as well as any amounts accrued for general and administrative costs. (n) Revenue Recognition The Company receives its revenue streams from three different sources; voyage or ‘spot’ charters; contracts of affreightment (“COA”), and time charters. Voyage charter and COA arrangements In the case of vessels contracted under voyage charters, the vessel is contracted for a voyage, or a series of voyages, between two or more ports and the Company is paid for the cargo transported. Revenue from COAs is recognized on the same basis as revenue from voyage charters, as they are essentially a series of consecutive voyage charters. Payment from voyage charters and COAs is due upon discharge of the cargo at the discharge port. We recognize revenue on a load port to discharge port basis and determined percentage of completion for all voyage charters and COAs on a time elapsed basis. The Company believes that the performance obligation towards the customer starts to become satisfied once the cargo is loaded and the obligation becomes completely satisfied once the cargo has been discharged at the discharge port. Under this revenue recognition standard, the Company has identified certain costs incurred to fulfill a contract with a charterer, which are costs incurred following the commencement of a contract or charter party but before the loading of the cargo commences. These directly related costs are generally fuel or any canal or port costs incurred to get the vessel from its position at inception of the contract to the load port to commence loading of the cargo. These costs are deferred and amortized over the duration of the performance obligation on a time basis. Voyage charters and COAs have an expected duration of one year or less. The Company has applied optional exemptions on adoption of the new revenue standard, as set out in Topic 606-10-50-14 Prior to the adoption of Topic 606, under a voyage charter or a COA the revenue was recognized on a discharge-to-discharge Time charter arrangements For vessels contracted under time charters, the arrangements are for a specified period of time. The Company receives a fixed charter rate per on-hire add-on (o) Other Comprehensive Income / (Loss) The Company follows the provisions of ASC 220 – Comprehensive Income, which requires separate presentation of certain transactions, which are recorded directly as components of stockholders’ equity. Comprehensive income is comprised of net income/(loss) and foreign currency translation gains and losses. (p) Voyage Expenses and Vessel Operating Expenses When the Company employs its vessels on time charter, it is responsible for all the operating expenses of the vessels, such as crew costs, stores, insurance, repairs and maintenance. In the case of voyage charters, the vessel is contracted only for a voyage between two or more ports, and the Company pays for all voyage expenses in addition to the vessel operating expenses. Voyage expenses consist mainly of in-port (q) Repairs and Maintenance All expenditures relating to routine maintenance and repairs are expensed when incurred. (r) Insurance The Company maintains hull and machinery insurance, war risk insurance, protection and indemnity insurance coverage, increased value insurance, demurrage and defense insurance coverage in amounts considered prudent to cover normal risks in the ordinary course of its operations. Premiums paid in advance to insurance companies are recognized as prepaid expenses and recorded as a vessel operating expense over the period covered by the insurance contract. In addition, the Company maintains Directors and Officers insurance. When the Company has enforceable insurance in place, a receivable is recognized for an insured event if realization is probable. We apply judgement that an insurance recovery is probable when the insurer has confirmed that a claim is covered by insurance, the claim has been successful, and an amount will be paid to the Company. If the insurance receivable realization is probable, the receivable is measured as the lesser of (a) the recognized loss from the insurance event or (b) the probable recovery from the insurer. Subsequent receipt of the receivable is typically within a twelve month period, and insurance receivables are classified as current on our consolidated balance sheets. If the recoverability of the insurance claim is subject to dispute then there is a rebuttable presumption that realization is not probable. (s) Share-Based Compensation The Company records as an expense in its financial statements the fair value of all equity-settled stock-based compensation awards. The terms and vesting schedules for share-based awards vary by type of grant. Generally, the awards vest subject to time- based conditions. Compensation expense is recognized ratably over the service period. (t) Critical Accounting Estimates We prepare our consolidated financial statements in accordance with U.S. GAAP, which requires us to make estimates in the application of our accounting policies based on our best assumptions, judgments and opinions. On a regular basis, management reviews the accounting policies, assumptions, estimates and judgments to ensure that our consolidated financial statements are presented fairly and in accordance with U.S. GAAP. However, because future events and their effects cannot be determined with certainty, actual results could differ from our assumptions and estimates, and such differences could (u) Foreign Currency Transactions Substantially all of the Company’s cash receipts are in U.S. Dollars. The Company’s disbursements, however, are in the currency invoiced by the supplier. The Company remits funds in the various currencies invoiced. The non-U.S. The primary source of our foreign exchange gains and losses are the movements on our Norwegian Kroner denominated 2018 Bonds. The 2018 Bonds are translated into U.S. Dollars at each reporting date at the prevailing exchange rate at the end of the period. The movement in the foreign exchange rates between each reporting date will result in a foreign exchange gain or loss on the 2018 Bonds, which is shown as a single line on the face of the statement of operations. The foreign currency exchange gain on the 2018 Bonds for the year ended December 31, 2021, was $2.1 million, compared to a foreign currency exchange loss of $1.9 million for the year ended December 31, 2020 , and a foreign currency exchange gain of $1.0 for the year ended December 31, 2019. The aggregate amount of all foreign exchange movements recorded in net income for the year ended December 31, 2021, was a $2.9 million gain compared to a $1.7 million loss for the year ended December 31, 2020, and a $0.8 million gain for the year ended December 31, 2019. The movement was primarily as a result of the foreign currency translation, at the prevailing exchange rate, of the 2018 Bonds mentioned in the previous paragraph. (v) Derivative instruments Derivative instruments are initially recorded at fair value as either assets or liabilities in the accompanying balance sheets are subsequently remeasured to fair value at each reporting date, regardless of the purpose or intent for holding the derivative. The resulting derivative assets or liabilities are shown as a single line and are not netted off against one another on the face of the balance sheet. The method of recognizing the resulting gain or loss is dependent on whether the derivative contract qualifies for hedge accounting and has been designated as a hedging instrument. For derivative instruments that are not designated or that do not qualify as hedging instruments under ASC 815 – Derivatives and Hedging, the liability has been recognized as ‘Derivative liabilities’ on the balance sheet and changes in the fair value of the derivative financial instruments are recognized in earnings. Gains and losses from the Company’s non-designated non-designated (w) Income Taxes Navigator Holdings Ltd. and its Marshall Islands subsidiaries are currently not required to pay income taxes in the Marshall Islands on ordinary income or capital gains as they qualify as exempt companies. The Company has four wholly owned subsidiaries incorporated in the United Kingdom where the base tax rate is 19%. These subsidiaries provide services to affiliated entities within the group. The Company has a subsidiary in Poland where the base tax rate is 19%. The subsidiary earns management fees from fellow subsidiary companies. The Company The Company has a subsidiary in the United States of America where the base tax rate is currently 21%. The subsidiary owns a 50% interest in the Export Terminal Joint Venture, a pass through entity for U.S. tax purposes with the subsidiary liable for its share of the profits of the Marine Export Terminal. The Company has consolidated a VIE incorporated in Malta where the base tax rate is 35%. This VIE is the lessor entity for the sale and leaseback of Navigator Aurora The Company considered the income tax disclosure requirements of ASC 740 – Income Taxes, with regard to disclosing material unrecognized tax benefits; none were identified. The Company’s policy is to recognize accrued interest and penalties for unrecognized tax benefits as a component of tax expense. As of December 31, 2020, and 2021, there were no accrued interest and penalties for unrecognized tax benefits. Deferred taxation Deferred income tax assets and liabilities are recognized for the future tax consequences attributed to differences between the financial statements and tax basis of existing assets and liabilities using enacted rates applicable to the periods in which the differences are expected to affect taxable income. Deferred income tax balances included on the consolidated balance sheets reflect the effects of temporary differences between the carrying amounts of assets and liabilities and their tax basis and are stated at enacted tax rates expected to be in effect when taxes are actually paid or recovered. Deferred income tax assets represent amounts available to reduce income taxes payable on taxable income in future years. The recoverability of these future tax deductions is evaluated by assessing the adequacy of future taxable income, including the reversal of temporary differences and forecasted operating earnings. If it is deemed more likely than not that the deferred tax assets will not be realized, the Company provides for a valuation (x) Earnings Per Share Basic earnings per common share (“Basic EPS”) is computed by dividing the net income/(loss) available to common stockholders by the weighted average number of shares outstanding. Diluted earnings per common share (“Diluted EPS”) are computed by dividing the net income available to common stockholders by the weighted average number of common shares and dilutive common share equivalents then outstanding. Shares granted pursuant to the 2013 Restricted Stock Plan are the only dilutive shares, and these shares have been considered as outstanding since their respective grant dates for purposes of computing diluted earnings per share. These shares were antidilutive in the years ended December 31, 2019, 2020 and 2021 and thus not included in the calculation of diluted EPS in the last three years. (y) Related parties Parties are related if one party has the ability, directly or indirectly, to control the other party or exercise significant influence over the other party in making financial and operating decisions. Parties are also related if they are subject to common control or significant influence. (z) Segment Reporting Management internally evaluates the performance of the enterprise as a whole and not on the basis of separate business units or different types of charters. As a result, the Company has determined that it operates as one reportable segment. Since the Company’s vessels regularly move between countries in international waters over many trade routes, it is impractical to assign revenues or earnings from the transportation of international LPG and petrochemical products by geographic area. Other than two vessels involved in cabotage trade within Indonesia for the years ended Decem b er 31, 2021 (December 31, 2020: three vessels), our vessels operate on a worldwide basis and are not restricted to specific locations. As disclosed in Note 6—Operating revenue to our consolidated financial statements, there are two different revenue streams due to the nature of the contracts that we operate. The Company considers the equity method investments do not meet the criteria in ASC 280 to be separate reportable segments. (aa) Recent Accounting Pronouncements The following accounting standards issued as of April 2 8 In January 2021, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2021-01, pay-variable Accounting Standards Updates, recently adopted ASU 2016-13 In June 2016, FASB issued ASU 2016-13, held-to-maturity available-for-sale In May 2019, the FASB issued ASU No. 2019-05 In April 2019, the FASB issued ASU No. 2019-04, No. 2018-19, 326-20. 2019-04, In May 2019, the FASB issued ASU 2019-05, Financial Instruments—Credit Losses (Topic 326): Targeted Transition Relief which provides transition relief for entities adopting the credit losses standard, ASU 2016-13. Specifically, ASU 2019-05 amends ASU 2016-13 to allow companies to irrevocably elect, on adoption of ASU 2016-13, the fair value option for financial instruments that were previously recorded at amortized cost, are within the scope of the guidance in ASC 326-20, are eligible for the fair value option under ASC 825-20 and are not held-to-maturity debt securities. In May 2019, the FASB issued ASU 2019-11, 2019-11 2016-13. ASC 842 (Leases) On January 1, 2019, the Company adopted ASU 2016-02, on-balance 842-10-65-1(f) use-of-hindsight The lessor accounting under ASC 842 has not fundamentally changed from legacy US GAAP (Topic 840). Under new guidance lessees and lessor will disclosure key information about their leasing transactions. The Company’s management concludes that Unigas International B.V. (“Pool Manager”) is Principal in the Unigas Pool arrangement, and it has also identified that its contract regarding vessels contributed to the Unigas pool contain a lease in accordance with ASC 842

Business Combinations

Business Combinations	12 Months Ended
	Dec. 31, 2021
Business Combinations [Abstract]
Business Combinations	3. Business Combinations On August 4, 2021, the Company completed the Ultragas Transaction by acquiring two entities, Othello Shipping, with its 18 wholly vessel owning subsidiaries, and Ultragas ApS (the vessels’ operator). Ultragas has a wholly owned subsidiary Ultraship ApS (an in-house share in the equity of Unigas Intl B.V. (a pool in which 11 of the 18 vessels acquired operated at the time of the acquisition); a share in the equity of Ultraship Crewing Philippines Inc. (“UCPI”, “UltraShip Crewing”), a marine services provider; and share in the equity of Ultraship Services Philippines Inc. (“USPI”), an IT, accounting and administrative support provider. The total consideration was $410.4 million, comprising $202.9 million in equity consideration to Ultranav ( million shares of the Company’s common stock a per share (closing price on August 4, 2021)) and debt and other liabilities assumed of $207.5 million. The following table summarizes the consideration transferred and the assets acquired and liabilities assumed as of the acquisition date. Amount Consideration Equity consideration $ 202,910 Fair value of consideration transferred $ 202,910 Net assets acquired: Handysize vessels 215,852 Smaller vessels 160,734 Cash and cash equivalents 17,477 Accounts receivable 7,071 Inventory 2,039 Other current assets 4,615 Equity method investments 2,580 Debt (192,695 ) Accounts payable (3,175 ) Accrued interest (1,602 ) Other current liabilities (3,982 ) Other long-term liabilities (6,004 ) Net assets acquired $ 202,910 The Company recorded the acquired assets and liabilities at fair value. The value s costs The estimated fair value of the acquired vessels was derived by using the discounted cash flow method under the income approach. The estimates and assumptions regarding expected cash flows require considerable judgment and are based upon historical experience, financial forecasts and industry trends and conditions, and reflect management’s assumptions and judgements regarding (i) expected future charter rates; (ii) expected future utilization rates; (iii) the estimated remaining useful lives of the vessels; and (iv) the discount rate applied to the estimated future cash flows. The revenues and net income of Ultragas included in the Consolidated Statement of Operations for the period ended December 31, 2021 , The unaudited proforma financial information is based on Navigator Holdings Ltd’s and Ultragas’ historical consolidated financial statements as adjusted to give effect to the acquisition of Ultragas. The following unaudited revenue and net income/(loss) gives effect to the Ultragas Transaction as if it had occurred on January 1, 2020. Year ended Year ended (in thousands) Revenues of the combined entity $ 437,957 $ 470,373 Net income/(loss) of the combined entity 4,056 (23,816 )

Derivative Instruments Accounte

Derivative Instruments Accounted for at Fair Value	12 Months Ended
	Dec. 31, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments Accounted for at Fair Value	4. Derivative Instruments Accounted for at Fair Value The Company uses derivative instruments in accordance with its overall risk management policy to mitigate our risk to the effects of unfavorable fluctuations in foreign exchange and interest rate movements. The Company held no derivatives designated as hedges as of December 31, 2020, and 2021. Fair value is a market-based measurement that is determined based on assumptions that market participants would use in pricing an asset or a liability. The fair value accounting standard establishes a three tier fair value hierarchy, which prioritizes the inputs used in the valuation methodologies in measuring fair value: Level 1—Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets. Level 2—Include other inputs that are directly or indirectly observable in the marketplace. Level 3—Unobservable inputs which are supported by little or no market activity. Interest Rate risk On July 2, 2020, the Company entered into floating-to-fixed 3-month 360-day 360-day The fair value of these non-designated non-current (December 31, 2020, a fair value liability of $0.1 million) and unrealized gains (December 31, 2020, an unrealized loss of $0.1 million On August 4, 2021, following the Ultragas Transaction, the Company has assumed a number of existing loan facilities with associated fixed interest rate swaps. These fixed interest rate swaps are entered into with two of the financial institutions with 6-month 360-day 360-day The fair value of these non-designated non-current liability On December 10, 2021, the Company entered into new floating to fixed interest rate swap agreements on our September 2020 Secured Revolving Credit Facility with Nordea Bank ABP, National Australia Bank Limited, ABN AMRO Bank N.V. and BNP Paribas S.A. with a termination date of September 2025 to run concurrently with the facility. The interest rate receivable by the Company under these interest rate swap agreements is 3-month 360-day 360-day The fair value of these non-designated non-current All interest rate swaps above are remeasured to fair value at each reporting date and have been categorized as level two on the fair value measurement hierarchy. Foreign Currency Exchange Rate risk All foreign currency-denominated monetary assets and liabilities are revalued and are reported in the Company’s functional currency based on the prevailing exchange rate at the end of the period. These foreign currency transactions fluctuate based on the strength of the U.S. Dollar relative to the NOK and are included in our results of operations. The primary source of our foreign exchange gains and losses are the movements on our NOK-denominated 2018 Bonds, which we have mitigated through the cross-currency interest rate swap. The remeasurement of all foreign currency-denominated monetary assets and liabilities at each reporting date results in unrealized foreign currency exchange differences but do not impact our cash flows. The Company entered into a cross-currency interest rate swap agreement concurrently with the issuance of its NOK denominated senior secured bonds (please read Note 12—Senior Secured Bond to our consolidated financial statements) and pursuant to this swap, the Company receives the principal amount of NOK 600 million in exchange for a payment of a fixed amount of $71.7 million on the maturity date of the swap. In addition, at each quarterly interest payment date, the cross-currency interest rate swap exchanges a receipt of floating interest of 6.0% plus 3-month 3-month The fair value of this non-designated ). The remeasurement to fair value has no impact on the cash flows at the reporting date except for the effect on restricted cash. Amounts included in restricted cash (if any) represent those required to be set aside as collateral by a contractual agreement with a banking institution for the forecast future liability on the cross-currency interest rate swap agreement at the reporting date. The Company ha offset the fair value of the derivative with any cash collateral account, notwithstanding there is a master netting agreement in place. Credit risk The Company is exposed to credit loss in the event of non-performance by the counterparty to the cross-currency interest rate swap agreement. In order to minimize counterparty risk, the Company only enters into derivative transactions with counterparties that are reputable financial institutions, highly rated by a recognized rating agency. As of December 31, 2021, there was immaterial credit risk as the cross-currency interest rate swap and the interest rate swaps were in a liability position from the perspective of the Company. The fair values of our interest rate swap agreements and the cross-currency interest rate swap is the estimated amount that we would pay to sell or transfer the swap at the reporting date, taking into account current interest rates and the current credit worthiness of the swap counterparties, in addition to foreign exchange rates for the cross-currency swap agreement. The estimated amount is the present value of future cash flows, adjusted for credit risk. The Company transacts all of these derivative instruments through investment-grade rated financial institutions at the time of the transaction. It is possible that the amount recorded as a derivative asset or liability could vary by a material amount in the near term if there is volatility in the credit markets or if credit risk were to change significantly. The fair value of our interest rate swap agreements and cross-currency interest rate swap agreement at the end of each period is most significantly affected by the interest rate implied by the benchmark interest yield curve, including its relative steepness and the forward foreign exchange rates respectively. Interest rates and foreign exchange rates have experienced significant volatility in recent years in both the short and long term. While the fair value of our swap agreements is typically more sensitive to changes in short-term rates, significant changes in the long-term benchmark interest, foreign exchange rates and the credit risk of the counterparties or the Company also materially impact the fair values of our swap agreements. The following table includes the estimated fair value of those assets and liabilities that are measured at fair value on a recurring basis as of December 31, 2020 and 2021. December 31, 2020 December 31, 2021 Fair Value Hierarchy Level Fair Fair Value Fair Value (in thousands) Cross-currency interest rate swap agreement Level 2 $ (2,896 ) $ (5,052 ) Interest rate swap agreements liabilities Level 2 (111 ) (3,748 ) Interest rate swap agreements assets Level 2 — 579

Fair Value of Financial Instrum

Fair Value of Financial Instruments Not Accounted For at Fair Value	12 Months Ended
	Dec. 31, 2021
Investments, All Other Investments [Abstract]
Fair Value of Financial Instruments Not Accounted For at Fair Value	5. Fair Value of Financial Instruments Not Accounted For at Fair Value The principal financial assets of the Company as of December 31, 2020, and 2021 consist of cash, cash equivalents and restricted cash and accounts receivable. The principal financial liabilities of the Company as of December 31, 2020 and 2021 consist of accounts payable, accrued expenses and other liabilities, secured term loan facilities, revolving credit facilities, the 2020 Bonds and the 2018 Bonds. The carrying values of cash, cash equivalents and restricted cash, accounts receivable, accounts payable, accrued expenses and other liabilities are reasonable estimates of their fair value due to the short-term nature or liquidity of these financial instruments. Fair value is a market-based measurement that is determined based on assumptions that market participants would use in pricing an asset or a liability. The fair value accounting standard establishes a three tier fair value hierarchy, which prioritizes the inputs used in the valuation methodologies in measuring fair value: Level 1—Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets. Level 2—Include other inputs that are directly or indirectly observable in the marketplace. Level 3—Unobservable inputs which are supported by little or no market activity. The 2020 Bonds and the 2018 Bonds are classified as a level two liability and the fair values have been calculated based on the most recent trades of the bond on the Oslo Børs prior to December 31, 2021. Theses trades are infrequent and therefore not considered to be an active market. The 2018 Bonds are denominated in Norwegian Kroner (“NOK”) and the fair value has been translated to the functional currency of the Company using the prevailing exchange rate as at December 31, 2021. The fair value of secured term loan facilities and revolving credit facilities is estimated to approximate the carrying value in the balance sheet since it bears a variable interest rate, which is reset on a quarterly basis. This has been categorized at level two on the fair value measurement hierarchy as at December 31, 2021. The following table includes the estimated fair value and carrying value of those assets and liabilities where the fair value does not approximate to carrying value. The table excludes cash, cash equivalents and restricted cash, accounts receivable, accounts payable, accrued expenses and other liabilities because the fair value approximates carrying value and, for accounts receivable and payable, are due in one year or less. December 31, 2020 December 31, 2021 Fair Value Hierarchy Level Fair Carrying Fair Value Carrying Fair Value (in thousands) 2018 Bonds (note 12) Level 2 (70,299 ) (72,672 ) (68,154 ) (69,970 ) 2020 Bonds (note 13) Level 2 (100,000 ) (103,500 ) (100,000 ) (104,000 ) Secured term loan facilities and revolving credit facilities (note 11) Level 2 (685,930 ) (685,930 ) (815,942 ) (815,942 )

Operating Revenues

Operating Revenues	12 Months Ended
	Dec. 31, 2021
Revenue from Contract with Customer [Abstract]
Operating Revenues	6. Operating Revenues The following table compares our operating revenues by the source of revenue stream for the years ended December 31, 2019 Year ended 2019 2020 2021 (in thousands) Operating revenues: Time charters $ 168,641 $ 177,762 $ 190,420 Voyage charters 132,744 141,903 162,502 Time charters from Luna Pool collaborative arrangements — 606 1,283 Voyage charters from Luna Pool collaborative arrangements — 12,224 25,272 Operating revenues from Unigas Pool — — 27,004 Total operating revenues $ 301,385 $ 332,495 $ 406,481 Time charter revenues As of December 31, 2021, 26 of the Company’s 45 operated vessels, were subject to time charters, 19 of which will expire within one year, two of which will expire within three years, and five which will expire after more than five years from the balance sheet date. (December 31, 2020: 19 of the Company’s 38 operated vessels, were subject to time charters, 11 (in thousands) 2022: $ 121,571 2023: $ 77,541 2024: $ 61,319 2025: $ 61,174 2026: $ 34,539 2027 onwards: $ 5,347 For time charter revenues accounted for under Topic 842, the amount of accrued income on the Company’s consolidated balance sheets was $4.5 million (December 31, 2020: $8.4 million). The amount of hire payments received in advance under time charter contracts, recognized as a liability and reflected within deferred income on the Company’s consolidated balance sheets was $17.0 million (December 31, 2020: $10.0 million). Deferred income allocated to time charters will be recognized ratably over time, which is expected to be within one month from December 31, 2021. Voyage Charter revenues Voyage charter revenues, which include revenues from contracts of affreightment, are shown net of address commissions. As of December 31, 2021, for voyage charters and contracts of affreightment, services accounted for under Topic 606, the amount of contract assets reflected within accrued income on the Company’s consolidated balance sheets was $1.3 million (December 31, 2020: $11.4 million). Changes in the contract asset balance at the balance sheet dates reflect income accrued after loading of the cargo commences but before an invoice has been raised to the charterer, as well as changes in the number of the Company’s vessels contracted under voyage charters or contracts of affreightment. The amount of contract liabilities reflected within deferred income on the Company’s consolidated balance sheets was $1.5 million (December 31, 2020: $1.6 million). The opening and closing balance of receivables from voyage charters and contracts of affreightment was $3.3 million and $11.1 million respectively as of December 31, 2021 (December 31, 2020: $4.2 million and $3.3 million respectively) and are reflected within net accounts receivable on our consolidated balance sheets. The amount allocated to costs incurred to fulfill a contract with a charterer, which are costs incurred following the commencement of a contract or charter party but before the loading of the cargo commences was $0.6 million as of December 31, 2021 Voyage and Time charter revenues from Luna Pool collaborative arrangements: Revenues from the Luna Pool collaborative arrangements for year ended December 31, 2020, and 2021, which are accounted for under ASC 808 – Collaborative Arrangements, represent our share of pool net revenues generated by the other Pool Participant’s vessels in the Luna Pool. These include revenues from voyage charters and contracts of affreightment, which are accounted for under Topic 606 in addition to time charter revenues, which are accounted for under Topic 842

Vessels, net

Vessels, net	12 Months Ended
	Dec. 31, 2021
Vessels, net	7. Vessels, net Vessel Drydocking Total Cost January 1, 2020 $ 2,060,280 $ 36,228 $ 2,096,508 Additions 2,233 10,192 12,425 Write-offs of fully amortized assets — (6,766 ) (6,766 ) December 31, 2020 2,062,513 39,654 2,102,167 Vessel additions on acquisition 363,951 12,635 376,586 Additions 3,150 19,946 23,096 Transfer to assets held for sale (55,877 ) (3,515 ) (59,392 ) Disposals (4,299 ) (451 ) (4,750 ) Write-offs of fully amortized assets — (12,691 ) (12,691 ) Vessel impairments (63,581 ) — (63,581 ) December 31, 2021 $ 2,305,857 $ 55,578 $ 2,361,435 Accumulated Depreciation January 1, 2020 $ 468,403 $ 18,578 $ 486,981 Charge for the period 68,033 8,231 76,264 Write-offs of fully amortized assets — (6,766 ) (6,766 ) December 31, 2020 536,436 20,043 556,479 Charge for the period 76,481 11,562 88,043 Transfer to assets held for sale (32,460 ) (988 ) (33,448 ) Disposals (100 ) (100 ) (200 ) Write-offs of fully amortized assets — (12,691 ) (12,691 ) December 31, 2021 $ 580,357 $ 17,826 $ 598,183 Net Book Value December 31, 2019 $ 1,591,877 $ 17,650 $ 1,609,527 December 31, 2020 $ 1,526,077 $ 19,611 $ 1,545,688 December 31, 2021 $ 1,725,500 $ 37,752 $ 1,763,252 The cost and The net book value of vessels that serve as collateral for the Company’s secured bond, secured term loan and revolving credit facilities (Note 11 and Note 12 The cost and net book value of vessels that are included in the table above and are subject to financing arrangements (please read Note 10—Variable Interest Entities to the consolidated financial statements) was $83.6 million and $69.6 million, respectively, as of December 31, 2021. (December 31, 2020: $82.9 million and $71.0 million, respectively).

Assets held for sale

Assets held for sale	12 Months Ended
	Dec. 31, 2021
Assets held for sale [Abstract]
Assets held for sale	8. Assets held for sale 2021 (in thousands) As of January 1 — Reclassification from Vessels 25,944 As of December 31 25,944 At December 31, 2021, assets held for sale comprised of two vessels, Navigator Neptune Happy Bird non-related

Equity Method Investments

Equity Method Investments	12 Months Ended
	Dec. 31, 2021
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments	9. Equity Method Investments Interests in investments which are accounted for using the equity method and are recognized initially at cost and subsequently include the Company’s share of the profit or loss and other comprehensive income of equity-accounted investees. As of December 31, 2020, and 2021, we had the following participation in investments that are accounted for using the equity method: December 31, December 31, 2020 2021 Enterprise Navigator Ethylene Terminal L.L.C. (“Export Terminal Joint Venture”) 50 % 50 % Luna Pool Agency Limited. (“Pool Agency”) 50 % 50 % Unigas International B.V. (“Unigas”) — 33.33 % Dan Unity CO2 A/S — 50 % Export Terminal Joint Venture In January 2018, the Company entered into definitive agreements creating the Export Terminal Joint Venture. As of December 31, 2021, we had contributed to the Export Terminal Joint Venture $146.5 million being our total Cumulative interest and associated costs capitalized on the investment in the Export Terminal Joint Venture are being amortized over the estimated useful life of the Marine Export Terminal, which began commercial operations with the export of commissioning cargoes in December 2019. As of December 31, 2021, the unamortized difference between the carrying amount of the investment in the Export Terminal Joint Venture and the amount of the Company’s underlying equity in net assets of the Export Terminal Joint Venture was $6.1 million (December 31, 2020: $6.5 million). The costs amortized in the year ended December 31, 2021, were $0.4 million and are presented in the share of result of the equity method investments within our consolidated statements of operations. (December 31, 2019 and 2020: nil and $0.3 million, respectively) Equity method gains, excluding amortized costs, recognized in the share of result of equity method investments for the year ended December 31, 2021, were million (December 31, 2020 and 2019: equity method gain of million and an equity method loss of million, respectively). Luna Pool Agency Limited In March 2020, the Company collaborated with Pacific Gas Pte. Ltd. and Greater Bay 2021 balance sheets. The Pool Agency has no activities other than that as a legal custodian of the Luna Pool bank account and there will be no variability in its financial results, as it has no income and its minimal operating expenses are reimbursed by the Pool Participants. Unigas International B.V. (‘Unigas’) Unigas based in the Netherlands is a commercial and operational manager of seagoing vessels capable of carrying liquefied petrochemical and petroleum gases on a worldwide basis. Unigas International is operator of the Unigas pool. The Company owns 33.33 % interest equity interests in Unigas and accounts for it using the equity method. It was recognized initially at fair value and subsequent to initial recognition, the consolidated financial statements will include the Company’s share of the profit or loss and other comprehensive income of equity accounted entity. The Company acquired the investment as part of the Ultragas Transaction on August 4, 2021. Dan Unity O2 A/S On June 3, 2021, the Company’s subsidiary, Ultragas entered into a shareholder agreement creating an equally owned joint venture, Dan Unity CO2 A/S, a Danish entity, with the aim of undertaking commercial and technical projects relating to seaborne transportation of CO2. The Company acquired the investment as part of the Ultragas Transaction We account for our investment using the equity method as our ownership interest is 50% and we exercise joint control over the Dan Unity CO2 A/S operating and financial policies. As of December 31, 2021, we have recognized the Company’s initial investment at cost and subsequent to initial recognition, the consolidated financial statements will include the Company’s share of the profit or loss and other comprehensive income of equity accounted investees, until the date on which joint control ceases. We disclose our proportionate share of profits and losses from equity method unconsolidated affiliates in the statement of operations and adjust the carrying amount of our equity method investments on the balance sheet accordingly. The table below represents movement in the Company’s equity method investments, as of December 31, 2019, 2020, and 2021: 2019 2020 2021 (in thousands) Equity method investments at January 1 $ 42,462 $ 130,660 $ 148,665 Contributions to equity method investments 84,500 17,000 4,000 Equity method investments – additions — — 2,580 Share of results (1,126 ) 651 11,147 Distributions received from equity method investments — — (16,183 ) Capitalized interest and deferred financing costs 4,824 354 — Total equity method investments at December 31 $ 130,660 $ 148,665 $ 150,209

Variable Interest Entities

Variable Interest Entities	12 Months Ended
	Dec. 31, 2021
Variable Interest Entities Disclosure [Abstract]
Variable Interest Entities	10. Variable Interest Entities As of December 31, 2020, and 2021, the Company has consolidated 100% of PT Navigator Khatulistiwa, a VIE for which the Company is deemed to be the primary beneficiary, i.e. it has a controlling financial interest in this entity with the power to direct the activities of a VIE that most significantly impact the entity’s economic performance and has the right to residual gains or the obligation to absorb losses that could potentially be significant to the VIE. The Company owns 49% of the VIE’s common stock, all of its secured debt and has voting control. All economic interests in the residual net assets reside with the Company. By virtue of the accounting principle of consolidation, transactions between PT Navigator Khatulistiwa and the Company are eliminated on consolidation. PT Navigator Khatulistiwa had total assets and liabilities, as of December 31, 2021, of $139.1 million and $18.5 million, respectively. (December 31, 2020: $125.9 million and $9.5 million respectively). On October 21, 2019, the Company entered into a sale and leaseback to refinance one of its vessels, Navigator Aurora Navigator Aurora As of December 31, 2020 and 2021, the Company has consolidated 100% of OCY Aurora Ltd., the lessor variable interest entity (‘‘lessor VIE’’) that we have leased Navigator Aurora Navigator Aurora The Company has performed an analysis and concluded that the Company exercises power through the exercise of the call options in the lease agreement. The call options, although not an activity of the SPV, if exercised would significantly impact the SPV’s economic performance as the SPV owns no other revenue generating assets. The options transfer to the Company the right to receive benefits as they are agreed at a predetermined price. The SPV is protected from decreases in the value of the vessel, as if the vessel’s market value were to decline, the call option provides the SPV protection up to the point where it would not be economically viable for the Company to exercise the option. In addition, the Company has the power to direct decisions over the activities and care of the vessel which directly impact its value such as for the day-to-day commercial, technical management and operation of the vessel. The lessor VIE had total assets and liabilities, as of December 31, 2021, of $58.9 million and $55.5 million, respectively. (December 31, 2020: $63.5 million and $61.7 million respectively). The assets and liabilities of the lessor VIE that most significantly impact the Company’ consolidated balance sheets and the financial statement line items in which they are presented, as of December 31, 2020 and 2021, are as follows: December 31, December 31, 2020 2021 (in thousands) Assets Cash, cash equivalents and restricted cash $ 215 $ 124 Prepaid expenses and other current assets — 324 Liabilities Amounts due to related parties, current $ (229 ) (197 ) Amounts due to related parties, non-current (61,361 ) (54,767 ) $ (61,590 ) $ (54,964 ) The most significant impact of the lessor VIE’ operations on the Company’ consolidated statements of operations is interest expense of $1.2 million for the year ended December 31, 2021 (December 31, 2020: $1.8 million). The most significant impact of the lessor VIE’ cash flows on the Company’ consolidated statements of cash flows is net cash used in financing activities of $6.3 million for the year ended December 31, 2021 (December 31, 2020: net cash used in financing activities of $6.8 million). On August 4, 2021, the Company completed the Ultragas Transaction. Ultragas owns a 25% and 40% share in equity of Ultraship Crewing Philippines Inc. (“UCPI”, “UltraShip Crewing”) and Ultraship Services Philippines Inc. (“USPI”), respectively. These companies are established primarily to provide marine services as principal or agent to ship owners, ship operators, managers engaged in international maritime business and business support services, respectively. The Company has determined that it has a variable interest in UCPI and USPI and is considered to be the primary beneficiary as a result of having a controlling financial interest in the entities and has the power to direct the activities that most significantly impact UCPI’s and USPI’s economic performance. As of December 31 2021 These amounts have been included in the Company’s consolidated balance sheet as of December 31, 2021 (December 31, 2020: $189.4 million and $71.2 million, respectively).

Secured Term Loan Facilities an

Secured Term Loan Facilities and Revolving Credit Facilities	12 Months Ended
	Dec. 31, 2021
Debt Disclosure [Abstract]
Secured Term Loan Facilities and Revolving Credit Facilities	11. Secured Term Loan Facilities and Revolving Credit Facilities The table below represents the annual principal payments to be made under our term loans and revolving credit facilities after December 31, 2020 and 2021: December 31, December 31, (in thousands) Due within one year $ 67,936 $ 151,586 Due in two years 124,479 229,460 Due in three years 202,353 209,633 Due in four years 175,413 92,381 Due in five years 54,388 50,403 Due in more than five years* 61,361 82,479 Total secured term loans and revolving credit facilities $ 685,930 $ 815,942 Less: current portion 67,936 151,586 Secured term loan facilities and revolving credit facility, non-current $ 617,994 $ 664,356 * Includes amounts relating to the Navigator Aurora Facility held within a lessor entity (for which legal ownership resides with financial institutions) that we are required to consolidate under U.S. GAAP into our financial statements as a variable interest entity (Please read Note 10—Variable Interest Entities to our consolidated financial statements) Terminal Facility. Interest on amounts drawn is payable at a rate of U.S. LIBOR 300 The Terminal Facility is subject to quarterly repayments of between $3.4 million and $3.8 million, which commenced in March 202 specified amounts of excess cash flow, the receipt of performance liquidated damages pursuant to certain material contracts related to the Marine Export Terminal, the receipt of proceeds in connection with an event of loss (as defined in the Terminal Facility), the receipt of proceeds in connection with termination payments (as defined in the Terminal Facility), the receipt of proceeds in connection with certain dispositions by the Export Terminal Joint Venture, the incurrence of certain specified indebtedness, the inability to meet the conditions for paying a dividend for four or more consecutive quarters, dispositions of the Marine Terminal Borrower’s equity interests in the Export Terminal Joint Venture, the receipt of indemnity payments in excess of $500,000 and certain amounts of any loans outstanding upon the conversion date The loans under the Terminal Facility are secured by first priority liens on the rights to the Marine Terminal Borrower’s distributions from the Export Terminal Joint Venture, the Marine Terminal Borrower’s assets and properties and the company’s equity interests in the Marine Terminal Borrower Following completion of the Marine Export Terminal . The Terminal Facility also limits the Marine Terminal Borrower from, among other things, incurring indebtedness or entering into mergers and divestitures. The Terminal Facility also contains general covenants that will require the Marine Terminal Borrower to vote its interest in the Export Terminal Joint Venture to cause the Export Terminal Joint Venture to maintain adequate insurance coverage, maintain its property (but only to the extent the Export Terminal Borrower has the power under the organizational documents of the Marine Terminal Joint Venture to cause such actions). On May 6, 2021, the Company obtained a waiver from the lenders under the Terminal Facility, which is retrospective with effect from the date of its inception, to correct a technical inconsistency in the Terminal Facility, involving a restrictive covenant relating to taking affirmative action regarding the treatment of tax status of the borrower as a corporation for U.S. federal, state or local income tax purposes. The waiver requires among other things, within 90 days after the date of the waiver, the parties to the Terminal Facility to amend the credit agreement and other loan documentation to remediate the inconsistency and to set aside and fund a tax reserve, based on the subsequent three months’ expected tax liabilities. The terms of the waiver were complied with and the amendment entered into on August 4, 2021 January 2015 Secured Term Loan Facility. , 2015, the Company entered into a secured term loan facility with Credit Agricole Corporate and Investment Bank as agent as well as HSH Nordbank AG and NIBC Bank N.V. to refinance the April 2013 million facility were written off in full. The facility is fully drawn and as of December 31, 2021, the amount still outstanding was $ million which is repayable for each vessel tranche in quarterly installments of between $ million and $ million for from the date of each vessel drawdown followed by a final payment of between $ million and $ million after each term ends. During the year ended December 31, 2019, the Company entered into the March 2019 secured term loan facility which refinanced four of the vessels that were previously in the January 2015 secured term loan facility. This loan facility is secured by first priority mortgages on each of; Navigator Umbrio, Navigator Centauri, Navigator Ceres, Navigator Ceto Navigator Copernico all times of cash and cash equivalents in an amount equal to or greater than (i) $ 25.0 5 December 2015 Secured Revolving Credit Facility. . using October 2016 Secured Term Loan and Revolving Credit Facility. term of seven years from the first utilization date (expiring in November 2023) with a maximum principal amount of up to $220.0 million. The facility has an undrawn amount of $20.0 million from the revolving portion of the facility and as of December 31, 2021, the outstanding balance drawn on the secured term loan, newbuilding loan and revolving credit facility was $78.4 million which is repayable in 7 quarterly amounts of approximately $4.1 million, followed by a final repayment of $50.0 million on November 30, 2023. Interest on amounts drawn is payable at a rate of U.S. LIBOR plus 260 basis points per annum. The aggregate fair market value of the collateral vessels must be no less than 125% of the aggregate outstanding borrowing under the facility. This facility is secured by first priority mortgages on each of: Navigator Gemini Navigator Leo, Navigator Libra, Navigator Pegasus Navigator Phoenix Navigator Taurus Navigator Jorf 25.0 per annum based on any undrawn portion of the facility. As of December 31, 2021, the Company was in compliance with all covenants contained in this credit facility. June 2017 Secured Term Loan and Revolving Credit Facility. ) 2023 Interest on amounts drawn is payable at a rate of U.S. LIBOR plus 230 basis points per annum. The aggregate fair market value of the collateral vessels must be no less tha of the aggregate outstanding borrowing under the facility. The facility is secured by first priority mortgages on each of Navigator Galaxy, Navigator Genesis, Navigator Grace, Navigator Gusto, Navigator Glory, Navigator Capricorn, Navigator Scorpio Navigator Virgo million and (ii) per cent of the total indebtedness; b) a ratio of EBITDA to interest expense of not less than 2.5:1; and c) maintain a ratio of total stockholders’ equity to total assets of not less than %. The Company also pays a commitment fee of % per annum based on any undrawn portion of the facility. As of December 31, 2021 March 2019 Secured Term Loan Facility . On March 25 million (the “March 2019 Secured Term Loan Facility”), to partially re-finance million was drawn on March 28, 2019. The facility has a term of six years from the date of the agreement, therefore expiring March 2025 . It is fully drawn down and as of December 31, 2021, with an amount outstanding of This loan facility is secured by first priority mortgages on each of; Navigator Atlas, Navigator Europa, Navigator Oberon, Navigator Triton September 2020 Secured Revolving Credit Facility. The facility is due to mature in September 2024, but contains an option, subject to the consent of the Lenders, exercisable 12 to 36 months after the date of the agreement, to extend the maturity date of the facility by 12 months to September 2025. As of December 31, 2021, an amount of $185.0 million of the $210.0 million was drawn and outstanding, which was used to repay the December 2015 secured revolving credit facility and associated fees. Interest on the September 2020 secured revolving credit facility is payable quarterly at U.S. LIBOR plus 250 basis points. The facility has an undrawn amount of $ million as of December 31, 2021 . The available facility amount shall be reduced semi-annually on June 30 and December 31 by an amount of $ million followed by a final balloon payment on September 17, 2024, of $150.9 million. This loan facility is secured by first priority mortgages on each of Navigator Eclipse, Navigator Luga, Navigator Nova, Navigator Prominence Navigator Yauza T he financial covenants each as defined within the credit facility are: a) the maintenance at all times of cash and cash equivalents in an amount equal to or greater than (i) $ 35.0 5 b) the maintenance of the ratio of total stockholders’ equity to total assets (both as defined by the September 2020 Secured Revolving Credit Facility agreement) of not less than 30% and the aggregate fair market value of the collateral vessels must be no less than 125% of the aggregate outstanding borrowing under the facility. Interest on amounts drawn is payable at a rate of U.S. LIBOR plus 250 basis points per August 2021 Amendment and Restatement Agreement. , as part of the Ultragas Transaction, the Company entered into an Amendment and Restatement Agreement with Danmarks Skibskredit A/S relating to a previously is s million (the “August 2021 Amendment and Restatement Agreement” ) equal half yearly installments of approximately % for the remaining duration of the loan. The facility is secured by first priority mortgages on each of Happy Osprey, Happy Peregrine, Happy Pelican Happy Penguin the . On August 4, 2021, as part of the Ultragas Transaction, the Company became guarantor for the following four Senior Secured Term Loan Facilities, previously entered into by Othello Shipping Company S.A. or certain of its wholly owned vessel owning entities. DB Credit Facility A. Atlanticgas Shipping Inc. Balearicgas Shipping Inc. DB Credit Facility A Atlanticgas and Balearicgas April 2027 million which is repayable for each vessel tranche in half yearly installments of million for twelve years from the date of each vessel drawdown. Interest on amounts drawn is payable at a rate of U.S. LIBOR basis points per annum. As of December 31, 2021, the Company was in compliance with all covenants contained in this credit facility. This loan facility is secured by first priority mortgages on each of Atlanticgas and Balearicgas the Amended to the Term Loan Facility, dated August 3, 2021 are: a) the maintenance at all times of cash and cash equivalents in an amount equal to or greater than (i) , or (ii) 5 % of total indebtedness (as defined), as applicable; b) the maintenance of the ratio of total stockholders’ equity to total assets of not less than 30 % and the aggregate fair market value of the collateral vessels must be no less than 125 % of the aggregate outstanding borrowing under the facility. Santander Credit Facility A. On October 30, 2013, Adriaticgas Shipping Inc., Celticgas Shipping Inc. and Lalandia Shipping Company S.A entered into Finance Corporation for a maximum principal amount of $81.0 million (the “ Santander Credit Facility A ”), to finance three newbuild LPG carriers, Adriaticgas , Celticgas and Happy Albatross . The facility has a term of twelve years from the date of the vessels’ deliveries, therefore expiring in May 2027 $37.1 million which is repayable for each vessel tranche in half yearly installments of between $1.0 million and $1.2 million for twelve years from the date of each vessel drawdown. Interest on amounts drawn is payable at a rate of U.S. LIBOR plus 205 basis points per annum. As of December 31, 2021, the Company was in compliance with all covenants contained in this credit facility. This loan facility is secured by first priority mortgages on each of Adriaticgas , Celticgas and Happy Albatross as well as assignments of earnings and insurances on these secured vessels. The financial covenants each as defined within the Amended to the Term Loan Facility, dated August 3, 2021 are: a) the maintenance at all times of cash and cash equivalents in an amount equal to or greater than (i) $50.0 million, or (ii) 5% of total indebtedness (as defined), as applicable; b) the maintenance of the ratio of total stockholders’ equity to total assets of not less than 30 % and the aggregate fair market value of the collateral vessels must be no less than 125 % of the aggregate outstanding borrowing under the facility. DB Credit Facility B. On July 31, 2015, Beringgas Shipping Inc and Pacificgas Shipping Inc entered into a amount of $60.9 million (the “ DB Credit Facility B ”), to finance two newbuild LPG carriers , Beringgas and Pacificgas . The facility has a term of twelve years from the date of the vessels’ deliveries, therefore expiring in December 2028 It is fully drawn down as of December 31, 2021, with an amount outstanding of $36.8 million which is repayable for each vessel tranche in half yearly installments of $1.3 million for twelve years from the date of each vessel drawdown. Interest on amounts drawn is payable at a rate of U.S. LIBOR plus 205 basis points per annum. As of December 31, 2021, the Company was in compliance with all covenants contained in this credit facility. This loan facility is secured by first priority mortgages on each of Bering gas and Pacificgas as well as assignments of earnings and insurances on these secured vessels. The financial covenants each as defined within the Amended to the Term Loan Facility, dated August 3, 2021 are: a) the maintenance at all times of cash and cash equivalents in an amount equal to or greater than (i) % of total indebtedness (as defined), as applicable; b) the maintenance of the ratio of total stockholders’ equity to total assets of not less % and the aggregate fair market value of the collateral vessels must be no less % of the aggregate outstanding borrowing under the facility. Santander Credit Facility B. On July 31, 2015, Arcticgas Shipping Inc Falstria Shipping Company S.A Santander Credit Facility B Arcticgas Happy Avocet January 202 facility. This loan facility is secured by first priority mortgages on each of Arcticgas Happy Avocet % of total indebtedness (as defined), as applicable; b) the maintenance of the ratio of total stoc k % and the aggregate fair market value of the collateral vessels must be no less % of the aggregate outstanding borrowing under the facility. Navigator Aurora Facility. Navigator Aurora 3-month million). The Navigator Aurora Facility is subordinated to a further bank loan where OCY Aurora Ltd. is the guarantor and Navigator Aurora Navigator Aurora 2021 value The following table shows the breakdown of secured term loan facilities and total deferred financing costs split between current and non-current December 31, December 31, (in thousands) Current Liability Current portion of secured term loan facilities $ 67,936 $ 151,586 Less: current portion of deferred financing costs (2,274 ) (3,016 ) Current portion of secured term loan facilities, net of deferred financing costs $ 65,662 $ 148,570 Non-Current Secured term loan facilities and revolving credit facilities net of current portion* $ 617,994 $ 664,356 Less: non-current (4,183 ) (4,689 ) Non-current non-current $ 613,811 $ 659,667 * Includes amounts relating to the Navigator Aurora Facility held within a lessor entity (for which legal ownership resides with a financial institution) that we are required to consolidate under U.S. GAAP into our financial statements as a variable interest entity Please read Note 10—Variable Interest Entities to our consolidated financial statements.

Senior Secured Bond

Senior Secured Bond	12 Months Ended
	Dec. 31, 2021
Senior Secured/Unsecured Bond	12. Senior Secured Bond On November 2, 2018, the Company issued senior secured bonds in an aggregate principal amount of NOK 600 million with Nordic Trustee AS as the bond trustee (the “2018 Bonds”). The were used to 3-month 360-day Interest is payable quarterly in arrears on February 2, May 2, August 2 and November 2. The 2018 Bonds were secured, prior to the sale of Navigator Neptune, by four of the Company’s ethylene capable semi-refrigerated liquefied gas carriers. These On the same date, the Company entered into a cross-currency interest rate swap agreement with Nordea Bank Abp (“Nordea”), with a termination date of November 2, 2023, to run concurrently with the 2018 Bonds. The interest rate payable by the Company under this cross-currency interest rate swap agreement is 6.608% plus 3-month million. The Company may redeem the 2018 Bonds, in whole or in part, at any time. Any 2018 Bonds redeemed until November 1, 2022, are Additionally, upon the occurrence of a “Change of Control Event” (as defined in the agreement governing the 2018 2018 2018 % of par, plus accrued interest. The financial covenants each as defined within the bond agreement are: (a) The issuer shall ensure that the Group (meaning “the Company and its % (as defined in the 2018 Bond Agreement). As of December 31, 2021, the Company was in compliance with all covenants for the 2018 Bonds. The 2018 Bond Agreement provides that we may declare dividends so long as such dividends do not exceed of our cumulative consolidated net profits after taxes from January 1, 2020. The 2018 Bond Agreement also limits us and our subsidiaries from, among other things, entering into mergers and divestitures, engaging in transactions with affiliates or incurring any additional liens which would have a material adverse effect. In addition, the 2018 Bond Agreement includes a put option exercisable following a change of control and customary events of default, including those relating to a failure to pay principal or interest, a breach of covenant, false representation and warranty, a cross-default to other indebtedness, the occurrence of a material adverse effect, or our insolvency or dissolution. The following table shows the breakdown of our senior secured bond and total deferred financing costs as of December 31, 2020, and 2021: December 31, December 31, (in thousands) Senior Secured Bond Total Bond $ 70,299 $ 68,154 Less deferred financing costs (719 ) (466 ) Total Bond, net of deferred financing costs $ 69,580 $ 67,688
2018 Senior Secured Bonds [Member]
Senior Secured/Unsecured Bond	13. Senior Unsecured Bonds On September 10, 2020, the Company issued senior unsecured bonds in an aggregate principal amount of $100.0 million with Nordic Trustee AS as the bond trustee (the “2020 Bonds”). The net proceeds of the issuance of the 2020 Bonds were used to redeem in full all of our outstanding previously issued 2017 Bonds. The 2020 Bonds are governed by Norwegian law and listed on the Nordic ABM which is operated and organized by Oslo Børs ASA. The redemption of the 2017 Bonds is accounted for as a debt extinguishment and the issuance of the 2020 Bonds is treated as the issuance of new debt. On redemption of the 2017 Bonds, the Company recognized a loss on extinguishment of $0.5 million, being the difference between the reacquisition price of the debt and the net carrying amount of the extinguished debt. Issuance costs for the 2020 Bonds of $2.0 million have been deferred and are being amortized over the term of the 2020 Bonds using the effective rate method. Issuance costs for the 2020 Bonds of $ million have been deferred and are being amortized over the term of the 2020 Bonds using the effective rate method. The 2020 Bonds bear interest at a rate of 8.0% per annum and mature on September 10, 2025. Interest is payable semi-annually in arrears on March 10 and September 10. The 2020 Bonds are redeemable by the Company, in whole or in part, at any time. Any 2020 Bonds redeemed; up until September 9, 2023 will be priced at the aggregate of the net present value (based on the Norwegian government bond rate plus 50 basis points) September 10 2024 of par; from September 10, 2024 up until March 9, 2025, are redeemable % of par, and from March 10, 2025 to the maturity date are redeemable at 100% of par, in each case, in cash plus accrued interest. Additional financial covenants (each as defined within the bond agreement governing the 2020 Bonds (the “2020 Bond Agreement”)) are: (a) The issuer shall ensure that the Group (meaning “the Company and its subsidiaries”) maintains a minimum liquidity of no less than $35.0 million; and (b) maintain a Group equity ratio (as defined in the 2020 Bond Agreement) of at least 30%. As of December 31, 2021, the Company was in compliance with all covenants for the 2020 Bonds. The 2020 60.0 The following table shows the breakdown of our senior unsecured bonds and total deferred financing costs as of December 31, 2020 and 2021: December 31, December 31, (in thousands) Senior Unsecured Bonds Total 2020 Bonds $ 100,000 100,000 Less deferred financing costs (1,842 ) (1,449 ) Total Bonds, net of deferred financing costs $ 98,158 $ 98,551

Loss per Share

Loss per Share	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Loss per Share	14. Loss per Share Basic loss per share is calculated by dividing the net income/(loss) available to common shareholders by the average number of common shares outstanding during the periods. Diluted earnings per share is calculated by adjusting the weighted average The following table shows calculation of both basic and diluted number of weighted average outstanding shares for the years ended December 31, 2019, 2020 and 2021 December 31, December 31, December 31, Basic and diluted loss available to common stockholders of Navigator Holdings Ltd (in thousands) (16,706 ) (443 ) (30,964 ) Basic weighted average number of shares 55,792,711 55,885,376 64,669,567 Effect of dilutive potential share options*: — — — Diluted weighted average number of shares 55,792,711 55,885,376 64,669,567 * Due to a loss for the years ended December 31, 2019, 2020

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2021
Share-based Payment Arrangement [Abstract]
Share-Based Compensation	15. Share-Based Compensation During 2013, the Company’s Board adopted the 2013 share in The 2013 Plan is administered by the Compensation Committee with certain decisi Share awards On March 17, 2021, the Company granted 29,295 restricted shares under the Navigator Holdings Ltd. 2013 Long-Term Incentive Plan (the “2013 Plan”) to non-employee During the year ended December 31, 2021, 30,380 shares that were granted to non-employee 12.04, 94,764 On March 19, 2020, the Company granted 37,975 restricted shares under the Navigator Holdings Ltd. 2013 Long-Term Incentive Plan (the “2013 Plan”) to non-employee During the year ended December 31, 2020, 27,125 shares that were granted to non-employee On March 20, 2019, the Company granted 32,550 restricted shares under 2013 Plan to non-employee During the year ended December 31, 2019, there were 29,898 shares that were previously granted to non-employee non-employee On August 14, 2019 non-employee Restricted share grant activity for the year ended December 31, 2020 and 2021 was as follows: Number of non-vested Weighted Weighted Balance as of January 1, 2020 329,156 $ 11.68 1.38 years Granted 79,172 7.90 Vested (89,888 ) 12.25 Forfeited (12,198 ) 11.54 Balance as of December 31, 2020 306,242 $ 10.54 0.93 years Granted 100,263 9.99 Vested (286,895 ) 10.66 Forfeited (16,123 ) 8.89 Balance as of December 31, 2021 103,487 $ 9.92 1.06 years We account for forfeitures as they occur. ecognized Share options Share options issued under the 2013 Plan are not exercisable until the third anniversary of the grant date and can be exercised up to the tenth anniversary of the date of grant. The fair value of each option is calculated on the date of grant based on the Black-Scholes valuation model. Expected The movements in the existing share options during the years ended December 31, 2020 2021 Options Number of Weighted Aggregate Balance as of January 1, 2020 349,936 $ 21.39 — Post vesting cancellations during the year (10,000 ) 20.82 — Balance as of December 31, 2020 339,936 21.40 $ — Post vesting cancellations during the year (29,080 ) 20.45 — Balance as of December 31, 2021 310,856 21.37 $ — There were 310,856 options exercisable as of December 31, 2021. The weighted average exercise price of the share options exercisable as of December 31, 2021, was $21.37. The weighted-average remaining contractual term of options outstanding and exercisable as of December 31, 2021, was 2.66 years. During the year ended December 31, 2021, the Company recognized no charge to share-based compensation costs (Year ended December 31, 2020: a credit of $77,364 and year ended December 31, 2019: a charge of $8,474) relating to options forfeited under the 2013 Plan. As of December 31, 2020, and December 31, During the year ended December 31, 2021, the Company set up an employee stock purchase plan whereby employees are entitled to purchase shares in the Company after a period of three years at a predetermined and discounted price set on June 16, 2021 (this date being the opening date of the scheme), of date.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	16. Commitments and Contingencies The contractual obligations schedule set forth below summarizes our contractual obligations as of December 31, 2021: 2022 2023 2024 2025 2026 Thereafter Total (in thousands) Secured term loan facilities and revolving credit facilities 151,586 229,460 209,633 92,380 50,403 27,602 761,064 2020 Bonds — — — 100,000 — — 100,000 2018 Bonds — 71,697 — — — — 71,697 Office operating leases 1 475 244 999 1,334 1,133 1,403 5,588 Navigator Aurora Facility 2 — — — — 54,767 — 54,767 Total contractual obligations $ 152,061 $ 301,401 $ 210,632 $ 193,714 $ 106,303 $ 29,005 $ 993,116 1 The Company occupies office space in London with a new lease commenced in January 2022 for a period of fifth The Company entered into a lease for office space in New York that now expires on May 31, 2022. The annual gross rent under this lease is approximately $0.4 million, subject to certain adjustments. The lease term for our representative office in Gdynia, Poland was revised during 2021 The Company occupies office space in Denmark with a lease commenced in September 2021 December 20 The weighted average remaining contractual lease term for the above four office leases on December 31, 2021 2 The Navigator Aurora Facility is a loan facility held within a lessor entity (for which legal ownership resides with financial institutions) that we are required to consolidate under U.S. GAAP into our financial statements as a variable interest entity. Please read Note 10—Variable Interest Entities to our consolidated financial statements.

Operating Lease Liabilities

Operating Lease Liabilities	12 Months Ended
	Dec. 31, 2021
Operating Lease Liabilities [Abstract]
Operating Lease Liabilities	17. Operating Lease Liabilities Lessee accounting Under ASU 2016-02 2019 non-lease 2021 20 The lease for our office in Poland is subject to annual indexation each January according to the Eurozone All Items Monetary Union Index of Consumer Prices (“MUICP”) index as quoted for the previous year. The lease payments relating to the Poland office lease are not remeasured at the beginning of each year, the effect of future increases in MUICP are recognized as part of lease-related costs in each year and classified as variable lease costs. For the years ended December 31, 2021, total operating lease costs were $0.7 million (December 31, 2020: $1.4 million), which include immaterial variable lease costs and are presented in General and Administrative costs within the consolidated statements of operations and in cash flows from operating activities within the consolidated statements of cash flows. The Company’s consolidated balance sheets include a ROU asset and a corresponding liability for operating lease contracts where the Company is a lessee. The discount rate used to measure the lease liability presented on the Company’s consolidated balance sheets is the incremental cost of borrowing since the rate implicit in the lease cannot be determined. The liabilities described below are for the Company’s offices in London, Gdynia, New York, and Denmark which are denominated in various currencies. At December 31, 2021, the weighted average discount rate across the three leases was 3.20% (December 31, 2020: 5.56%). At December 31, 2021, based on the remaining lease liabilities, the weighted average remaining operating lease term was 3.0 years (December 31, 2020: 5.6 years). The difference from the weighted average remaining contractual lease term arises from the mutual break option on the statements. A maturity analysis of the undiscounted cash flows of the Company’s operating lease liabilities as at December 31, 2020 2021 December 31, 2020 December 31, 2021 (in thousands) One year $ 1,572 $ 398 Two years 1,300 181 Three years 1,144 181 Four years 1,144 181 Five years 1,144 — Six years and thereafter 1,222 — Total undiscounted operating lease commitments $ 7,526 $ 941 Less: Discount adjustment (1,018 ) (38 ) Total operating lease liabilities $ 6,508 $ 903 Less: current portion (1,276 ) (381 ) Operating lease liabilities, non-current $ 5,232 $ 522

Concentration of Credit Risks

Concentration of Credit Risks	12 Months Ended
	Dec. 31, 2021
Risks and Uncertainties [Abstract]
Concentration of Credit Risks	18. Concentration of Credit Risks The Company’s vessels are chartered under either a time charter arrangement or voyage charter arrangement. Under a time charter arrangement, no security is provided for the payment of charter hire. However, payment is usually required monthly in advance. Under a voyage charter arrangement, a lien may sometimes be placed on the cargo to secure the payment of the accounts receivable, as permitted by the prevailing charter party agreement During 2021, two of our charterers contributed approximately each, and in aggregate 20.7% or million and ) . Other t The Company considers the equity method investments do not meet the criteria in ASC 280 to be separate reportable segments. As of December 31, 2020, and 2021, all of the Company’s cash, cash equivalents, restricted cash, and short-term investments were held by large financial institutions, highly rated by a recognized rating agency.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	19. Income Taxes Navigator Holdings Ltd and its vessel owning subsidiaries are incorporated in the Marshall Islands and under the laws of the Marshall Islands are not subject to tax on income or capital gains and no Marshall Islands withholding tax will be imposed on dividends paid by the Company to its stockholders. 2019 2020 2021 (Loss)/income before income taxes and share of result of equity method investments $ (15,129 ) $ 1,279 $ (38,394 ) Tax expense at statutory rate — — — Total statutory tax charge — — — Tax charge in U.S. subsidiaries — — 855 Tax charge in UK subsidiaries 199 416 566 Tax (credit)/charge in Polish subsidiary (65 ) 31 345 Tax charge in Singapore subsidiary 213 77 47 Tax charge in Danish subsidiary — — 74 Tax charge in Maltese VIE (note 10) 5 93 82 Total tax charge $ 352 $ 617 $ 1,969 Breakdown of current/deferred tax expense Current tax expense 524 489 1,264 Deferred tax expense (172 ) 128 705 Total corporate income tax $ 352 $ 617 $ 1,969 The total of all deferred tax assets included in our balance sheet as of December 31, 2021, wa 2020 The deferred tax asset of $22.0 million includes $21.5 million related to carry forwards associated with our Export Terminal Joint Venture which can be utilized against 80% of our future profits, in any one year, from the terminal operations. We have income tax carry forwards relating to our operations in Poland of approximately forwards. The U.S. losses relate to federal tax losses which can be carried forward indefinitely. The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities as of December 31, 2020, and 2021 2020 2021 Deferred tax asset Net operating losses carry forwards $ 19,601 $ 21,592 Other temporary differences — 388 Total deferred tax assets 19,601 21,980 Less valuation allowance (1,731 ) — Deferred tax asset, net of valuation allowance 17,870 21,980 Deferred tax liabilities Investment in joint venture 17,449 21,871 Other temporary differences 32 517 Total deferred tax liabilities $ 17,481 $ 22,388 Net deferred tax asset/(liability) 389 (408 ) The net deferred tax asset(liability) relates to deferred tax assets and liabilities in different jurisdictions.

Cash, Cash Equivalents and Rest

Cash, Cash Equivalents and Restricted Cash	12 Months Ended
	Dec. 31, 2021
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract]
Cash, Cash Equivalents and Restricted Cash	20. Cash, Cash Equivalents and Restricted Cash​​​​​​​ December 31, December 31, (in thousands) Cash, Cash Equivalents and Restricted Cash Cash and cash equivalents $ 59,056 $ 123,886 Cash and cash equivalents held by VIE (note 10) 215 337 Total cash, cash equivalents and restricted cash $ 59,271 $ 124,223 Our secured term loan facilities and revolving credit facilities require that the borrowers have liquidity (including undrawn available lines of credit with a maturity exceeding 12 months) of no less than (i) $25.0 million, $35.0 million, or $50.0 million, or (ii) 5% of Net Debt or total debt which was $49.2 million as of December 31, 2021, as applicable, whichever is greater. This requirement does not restrict the cash maintained within the company bank accounts but requires the group to hold no less than that amount of free cash within its bank accounts or treasury deposits . Included within total cash, cash equivalents and restricted cash as of December 31, 2021, is an amount of million relating to the cash belonging to the VIE’s million). Please read Note 10—Variable Interest Entities to our statements.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2021
Related Party Transactions [Abstract]
Related Party Transactions	21. Related Party Transactions The following table summarizes our transactions with related parties for the years ended December 31, 2020 and 2021: Year ended Year ended (in thousands) Net income / (expenses) Luna Pool Agency Limited $ — $ (30 ) Ocean Yield Malta Limited (1,827 ) (1,202 ) Ultranav Business Support ApS — (936 ) Naviera Ultranav Limitada — (25 ) Total $ (1,827 ) $ (2,193 ) The following table sets out the balances due from related parties as at December 31, 2020 and 2021: December 31, December 31, (in thousands) Due from Related Parties Luna Pool Agency Limited $ 11,853 $ 8,450 Unigas Pool — 8,049 Dan Unity — 109 Naviera Ultranav Limitada — 128 Total $ 11,853 $ 16,736 The following table sets out the balances due to related parties as at December 31, 2020 and 2021: December 31, 2020 December 31, 2021 (in thousands) Due to Related Parties Ocean Yield Malta Limited $ 61,448 $ 55,074 Naviera Ultranav Limitada — 27 Total $ 61,448 $ 55,101 Naviera Ultranav Limitada: On August 4, 2021, in connection with Ultragas Transaction, we issued ownership interest in us, to subsidiaries of Naviera Ultranav Limitada (“Ultranav”). As of December 31, 2021, Ultranav remained a 27.5% shareholder and was one of our principal shareholders. They may exert considerable influence on the outcome of matters on which our shareholders are entitled to vote, including the election of our directors to our board of directors and other significant corporate actions. Ultranav Business Support ApS: On August 4, 2021, in connection with the Ultragas Transaction, we entered into a Transitional Services Agreement (“TSA”) with Ultranav Business Support ApS (“UBS”) to provide back office services, such as accounting and payroll, IT, treasury, financial controlling, tax and compliance, communications and CSR, HR, administrative and branding). The company pays UBS a fee for services provided of

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2021
Stockholders' Equity Note [Abstract]
Stockholders' Equity	2 2 . S tockholders’ equity As of December 31, 2021, the Company’s authorized share capital consisted of 400,000,000 shares of common stock and 40,000,000 shares of preferred stock, each at par value of $0.01 per share. There were 77,180,429 shares of common stock issued and outstanding and no shares of preferred stock issued and outstanding at December 31, 2021. Each outstanding share of common stock entitles the holder to one vote on all matters submitted to a vote of shareholders. Subject to preferences that may be applicable to any outstanding preferred stock, holders of common stock are entitled to receive ratably all dividends, if any, declared by our board of directors out of funds legally available for dividends. Agreements governing our indebtedness impose restrictions on us, including, among other things, limiting our ability to pay dividends out of operating revenues generated by the vessels securing such indebtedness, redeem any shares or make any other payment to our equity holders, if there is a default under such agreements. Holders of common stock do not have conversion, redemption or preemptive rights to subscribe to any of our securities. The rights, preferences and privileges of holders of common stock are subject to the rights of the holders of any preferred stock which we may issue in the future.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	23. Subsequent Events On January 14, 2022, the Company sold one of its older vessels, Navigator Neptune Bond s Bond November On March 7, 2022 Happy Bird million. There was no mortgage associated with this vessel. On February 24, 2022, the Russian attack on Ukraine started. It may lead to further regional and international conflicts or armed action. It is possible that such conflict could disrupt supply chains and cause instability in the global economy. Additionally, the ongoing conflict could result in the imposition of further economic sanctions by the United States and the European Union against Russia. While much uncertainty remains regarding the global impact of the invasion, it is possible that such tensions could adversely affect our business, financial condition, results of operations and cash flows. We currently have four charterparties with a Russian counterparty that were entered into in 2012 and 2017, two of which expire in June 2022 and two expire in December 2023. These charterparties cannot be terminated without the consent of both parties, unless the counterparty was to become a sanctioned entity, or our dealings with that counterparty was to be prohibited by sanctions, which would render the charters void. Under the current circumstances of conflict between Russia and Ukraine, we intend not to renew these charterparties when they expire. We employ an aggregate of Russian and Ukrainian officers on board our vessels, many of whom are on the same vessels. We are monitoring this situation closely and there may be restrictions, logistical challenges or a complete inability to employ both nationalities in the near future. There are estimated Ukrainian Officers on the global fleet, which if unavailable in the future, would provide cost pressures from other nationalities or unavailability of suitably trained officers for our vessels.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2021
Basis of Presentation	(a) Basis of Presentation The consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Management has evaluated the Company’s ability to continue as a going concern and considered the conditions and events that could raise substantial doubt about the Company’s ability to continue as a going concern within 12 months after these financial statements are issued. As part of the assessment, management has considered the following; • the current financial condition and liquidity sources, including current funds available and forecasted future cash flows; • any likely effects of global epidemics or other health crises, such as the recent COVID-19 pandemic; and • the effects of the conflict in Ukraine on the Company’s business, including potential sanctions being imposed on the Company’s customers or on ports to which the Company’s vessels call. Management has determined that it is appropriate to continue to adopt the going concern basis in preparing the financial statements. The accompanying consolidated financial statements include the accounts of the Company and its subsidiaries and Variable Interest Entities (“VIE”) for which the Company is a primary beneficiary are also consolidated (See Note 10—Variable Interest Entities to our consolidated financial statements). All intercompany accounts and transactions have been eliminated in consolidation. On January 31, 2018, the Company announced the execution of definitive agreements creating a 50/50 joint venture with Enterprise Products Partners L.P. (the “Export Terminal Joint Venture”) to construct and operate an ethylene export marine terminal at Morgan’s Point, Texas on the Houston Ship Channel (the “Marine Export Terminal”). Enterprise Products Partners, L.P. is the sole managing member of the Export Terminal Joint Venture and it is also the operator of the Marine Export Terminal. Interests in joint ventures are accounted for using the equity method. They are recognized initially at cost, which includes interest capitalized from the terminal loan facility utilized during the construction phase. The capitalized interest will be amortized over the useful life of the terminal. Subsequent to initial recognition, the consolidated financial statements will include the Company’s share of the profit or loss and other comprehensive income (“OCI”) of equity-accounted investees, until the date on which joint control ceases. The Export Terminal Joint Venture is organized as a limited liability company and maintains separate ownership accounts, consequently we account for our investment using the equity method as our ownership interest is 50% and we exercise joint control over the investee’s operating and financial policies. We disclose our proportionate share of profits and losses from equity method unconsolidated affiliates in the statement of operations and adjust the carrying amount of our equity method investments on the balance sheet accordingly. In March 2020, the Company collaborated with Pacific Gas Pte. Ltd. and Greater Bay Gas Co. Ltd. to form and manage the Luna Pool. We refer to the Company and Greater Bay Gas Co. Ltd. collectively as the “Pool Participants”. As part of the formation of the Luna Pool, a new entity, Luna Pool Agency Limited, (“Pool Agency”) was established in May 2020. The investment in the Pool Agency created a 50/50 joint venture with Greater Bay Gas Co. Ltd. as outlined by Accounting Standards Codification (“ASC”) 323 – Investments -Equity Method and Joint Ventures (“ASC 323”). The Company’s investment in the Pool Agency is accounted for as an equity investment in accordance with the guidance within ASC 810 – Consolidation and ASC 323. Therefore, we account for our investment using the equity method as our ownership interest is 50% and we exercise joint control over the entity’s operating and financial policies. P In August 2021, as part of the Ultragas Transaction Dan-Unity U In August 2021, as part of the Ultragas Transaction P p m The Company has determined that it has a variable interest in UCPI and USPI (each as defined below), and is considered to be the primary beneficiary of each entity as a result of having a controlling financial interest in the entities and has the power to direct the activities that most significantly impact UCPI and USPI’s economic performance. The year ended December 31, 2020 includes an out of period adjustment in the consolidated statements of operations of an additional $0.5 million in general and administrative costs and a decrease of $0.8 million in interest expense, resulting in an overall decrease in the net loss for the year ended December 31, 2020 of $0.3 million, and in the consolidated balance sheets at December 31, 2020, an increase to the investment in the equity accounted joint ventures of $0.3 million. Management believes this out of period adjustment is not material to the annual consolidated financial statements for the year ending December 31, 2020 or any previously issued financial statements. Collaborative arrangements The Pool Participants manage and participate in the activities of the Luna Pool through an executive committee comprising equal membership from both Pool Participants. Certain decisions made by the executive committee as to the operations of the Luna Pool require the unanimous agreement of both participants with others requiring a majority of votes. The Company’s wholly owned subsidiary, NGT Services (UK) Limited acts as commercial manager (“Commercial Manager”) to the Luna Pool. Under the pool agreement, the Commercial Manager is responsible, as agent, for the marketing and chartering of the participating vessels, collection of revenues and paying voyage costs such as port call expenses, bunkers and brokers’ commissions in relation to charter contracts, but the vessel owners continue to be fully responsible for the financing, insurance, crewing and technical management of their respective vessels. The Commercial Manager receives a fee based on the net revenues of the Luna Pool, which is levied on the Pool Participants, which was a net amount of $ 0.4 0.2 Pool revenues and expenses within the Luna Pool are accounted for in accordance with ASC 808 – Collaborative Arrangements; Pool earnings (gross earnings of the pool less costs and overheads of the Luna Pool and fees to the Commercial Manager) are aggregated and then allocated to the Pool Participants in accordance with an apportionment for each participant’s vessels multiplied by the number of days each of their vessels are on hire in the pool during the relevant period and therefore the Company is exposed to risk and rewards dependent on the commercial success of the Luna Pool. We have concluded that the Company is an active participant due to its representation on the executive committee and the participation of the Commercial Manager, as is the other Pool Participant. We have presented our share of net income earned under the Luna Pool collaborative arrangement across a number of lines in our consolidated statements of operations. For revenues and expenses earned/incurred specifically by the Company’s vessels and for which we are deemed to be the principal, these are presented gross on the face of our consolidated statements of operations within operating revenues, voyage expenses and brokerage commissions. Our share of pool net revenues generated by the other Pool Participant’s vessels in the Luna Pool collaborative arrangement is presented on the face of our consolidated statements of operations within operating revenues – Luna Pool collaborative arrangements. The other Pool Participant’s share of pool net revenues generated by our vessels in the pool is presented on the face of our consolidated statements of operations within voyage expenses – Luna Pool collaborative arrangements. The portion of the Commercial Manager’s fee which is due from the other Pool Participant is presented on the face of our consolidated statements of operations as other income. The following table summarizes our net income generated from our participation in the Luna Pool for the years ended December 31, 2020 and 2021. Year ended Year ended (in thousands) Income / (expenses) Time and Voyage Charter Revenues $ 49,613 $ 90,592 Time and Voyage charter revenues from Luna Pool collaborative arrangements 12,830 26,555 Brokerage Commissions (804 ) (1,413 ) Voyage Expenses (14,966 ) (34,130 ) Voyage Expenses – Luna Pool collaborative arrangements (12,418 ) (20,913 ) Total net operating income from the Luna Pool 34,255 60,691 Other Income 199 367 Total net income from the Luna Pool $ 34,454 $ 61,058
Impairment of Vessels	(d) Impairment of Vessels Our vessels are reviewed for impairment when events or circumstances indicate the carrying amount of the vessel may not be recoverable. When such indicators are present, a vessel is tested for recoverability and we recognize an impairment loss if the sum of the future cash flows (undiscounted and excluding interest charges that will be recognized as an expense when incurred) expected to be generated by the vessel over its estimated remaining useful life are less than its carrying value. If we determine that a vessel’s undiscounted cash flows are less than its carrying value, we record an impairment loss equal to the amount by which its carrying amount exceeds its fair value. The new lower cost basis would result in a lower annual depreciation than before the impairment. At December 31, 2021, following a change to the estimated years, there were eight vessels that showed indications of impairment, as their individual carrying values were greater than their respective undiscounted cashflows. By applying a discounted cashflow method to those vessels, we assessed that these vessels be impaired by an aggregate amount of Considerations in making such an impairment evaluation include comparison of current carrying values to anticipated future operating cash flows, expectations with respect to future operations and other relevant factors. The estimates and assumptions regarding expected cash flows require considerable judgment and are based upon historical experience, financial forecasts and industry trends and conditions and reflect management’s assumptions and judgements regarding (i) expected future charter rates; (ii) expected future utilization rates; (iii) the estimated remaining useful lives of the vessels; and (iv) the discount rate applied to the estimated future cash flows.
Impairment of Equity Method Investments	(e) Impairment of Equity Method Investments The equity method investments are reviewed for indicators of impairment when events or circumstances indicate the carrying amount of the investment may not be recoverable. When such indicators are present, we determine if the indicators are ‘other than temporary’ to determine if an impairment exists. If we determine that an impairment exists, a discounted cash flow analysis is carried out based on the future cash flows expected to be generated over the investment’s estimated remaining useful life. The resulting net present value is compared to the carrying value and we would recognize an impairment loss equal to the amount by which the carrying amount exceeds its fair value.
Drydocking Costs	(f) Drydocking Costs Each vessel is required to be dry-docked dry-dockings dry-docking. dry-docking dry-docking
Intangible assets	(g) Intangible assets Intangible assets consist of software acquisition and associated costs of software modification to meet the Company’s internal needs. Intangible assets are amortized on a straight-line basis over the expected life of the software license, product or the expected duration that the software is estimated to contribute to the cash flows of the Company, estimated to be five years. Amortization of intangible assets is included in depreciation and amortization in the Consolidated Statements of Operations. Intangible assets are assessed for impairment when and if impairment indicators exist. An impairment loss is recognized if the carrying amount of an intangible asset is not recoverable and its carrying amount exceeds its fair value. No impairment has been recognized for the years ending December 31, 2021, 2020 and 2019.
Cash, Cash Equivalents and Restricted Cash	(h) Cash, Cash Equivalents and Restricted Cash The Company considers highly liquid investments, such as time deposits and certificates of deposit, with an original maturity of three months or less when purchased, to be cash equivalents. As of December 31, 2020, and 2021 and for the years then ended, the Company had balances in U.S. financial institutions in excess of the amounts insured by the Federal Deposit Insurance Corporation (“FDIC”). The Company also maintains cash balances in foreign financial institutions outside of the U.S. which are not covered by the FDIC. Amount s included in restricted cash may represent those required to be set aside as collateral by a contractual agreement with a banking institution for the forecast future liability on the cross-currency interest rate swap agreement at the reporting date, payable on maturity of our 2018 issued senior secured bonds (“2018 Bonds”). If the Norwegian Kroner depreciates relative to the U.S. Dollar beyond a certain threshold, we are required to place cash collateral with our swap providers. As of December 31, 2021, there collateral amount held with the swap provider (December 31, 2020 ). The amounts held as collateral within restricted cash are assessed against daily currency movements and are presented as current assets on the Company’s consolidated balance sheets. (h) Financial Instruments—Debt Securities
Accounts Receivable, net	(i) Accounts Receivable, net The Company carries its accounts receivable at cost less an allowance for expected credit losses. As of December 31, 2021, the Company evaluated its accounts receivable and established an allowance for expected credit losses, based on a history of past write-offs, collections and current credit conditions. As of December 31, 2021, the Company also considers future and reasonable and supportable forecasts of future economic conditions in its allowance for expected credit losses. The Company does not generally charge interest on past-due past-due
Bunkers and lubricant oils	(j) Bunkers and lubricant oils Bunkers and lubricant oils include bunkers (fuel), for those vessels under voyage charter, and lubricants. Under a time charter, the cost of bunkers is borne by and remains the property of the charterer. Bunkers and lubricant oils are accounted for on a first in, first out basis and are valued at cost.
Deferred Finance Costs	(k) Deferred Finance Costs Costs incurred in connection with obtaining secured term loan facilities, revolving credit facilities and bonds are recorded as deferred financing costs and are amortized to interest expense over the estimated duration of the related debt. Such costs include fees paid to the lenders or on the lenders’ behalf and associated legal and other professional fees. Under the Accounting Standards Update (ASU) 2015- 03, Interest—Imputation of Interest the Company has adopted the accounting standard (Subtopic 835-30)—simplifying
Deferred Income	(l) Deferred Income Deferred income is the balance of cash received in excess of revenue earned under voyage charter arrangements as of the balance sheet date. Deferred income also includes the unearned portion of time charter revenue invoices for which consideration has not been received as at the balance sheet date, but for which there is an unconditional right to receive such consideration before the performance obligation is satisfied.
Accruals and other liabilities	(m) Accruals and other liabilities Accrued expenses and other liabilities include all accrued liabilities relating to the operations of our vessels as well as any amounts accrued for general and administrative costs.
Revenue Recognition	(n) Revenue Recognition The Company receives its revenue streams from three different sources; voyage or ‘spot’ charters; contracts of affreightment (“COA”), and time charters. Voyage charter and COA arrangements In the case of vessels contracted under voyage charters, the vessel is contracted for a voyage, or a series of voyages, between two or more ports and the Company is paid for the cargo transported. Revenue from COAs is recognized on the same basis as revenue from voyage charters, as they are essentially a series of consecutive voyage charters. Payment from voyage charters and COAs is due upon discharge of the cargo at the discharge port. We recognize revenue on a load port to discharge port basis and determined percentage of completion for all voyage charters and COAs on a time elapsed basis. The Company believes that the performance obligation towards the customer starts to become satisfied once the cargo is loaded and the obligation becomes completely satisfied once the cargo has been discharged at the discharge port. Under this revenue recognition standard, the Company has identified certain costs incurred to fulfill a contract with a charterer, which are costs incurred following the commencement of a contract or charter party but before the loading of the cargo commences. These directly related costs are generally fuel or any canal or port costs incurred to get the vessel from its position at inception of the contract to the load port to commence loading of the cargo. These costs are deferred and amortized over the duration of the performance obligation on a time basis. Voyage charters and COAs have an expected duration of one year or less. The Company has applied optional exemptions on adoption of the new revenue standard, as set out in Topic 606-10-50-14 Prior to the adoption of Topic 606, under a voyage charter or a COA the revenue was recognized on a discharge-to-discharge Time charter arrangements For vessels contracted under time charters, the arrangements are for a specified period of time. The Company receives a fixed charter rate per on-hire add-on
Other Comprehensive Income / (Loss)	(o) Other Comprehensive Income / (Loss) The Company follows the provisions of ASC 220 – Comprehensive Income, which requires separate presentation of certain transactions, which are recorded directly as components of stockholders’ equity. Comprehensive income is comprised of net income/(loss) and foreign currency translation gains and losses.
Voyage Expenses and Vessel Operating Expenses	(p) Voyage Expenses and Vessel Operating Expenses When the Company employs its vessels on time charter, it is responsible for all the operating expenses of the vessels, such as crew costs, stores, insurance, repairs and maintenance. In the case of voyage charters, the vessel is contracted only for a voyage between two or more ports, and the Company pays for all voyage expenses in addition to the vessel operating expenses. Voyage expenses consist mainly of in-port
Repairs and Maintenance	(q) Repairs and Maintenance All expenditures relating to routine maintenance and repairs are expensed when incurred.
Insurance	(r) Insurance The Company maintains hull and machinery insurance, war risk insurance, protection and indemnity insurance coverage, increased value insurance, demurrage and defense insurance coverage in amounts considered prudent to cover normal risks in the ordinary course of its operations. Premiums paid in advance to insurance companies are recognized as prepaid expenses and recorded as a vessel operating expense over the period covered by the insurance contract. In addition, the Company maintains Directors and Officers insurance. When the Company has enforceable insurance in place, a receivable is recognized for an insured event if realization is probable. We apply judgement that an insurance recovery is probable when the insurer has confirmed that a claim is covered by insurance, the claim has been successful, and an amount will be paid to the Company. If the insurance receivable realization is probable, the receivable is measured as the lesser of (a) the recognized loss from the insurance event or (b) the probable recovery from the insurer. Subsequent receipt of the receivable is typically within a twelve month period, and insurance receivables are classified as current on our consolidated balance sheets. If the recoverability of the insurance claim is subject to dispute then there is a rebuttable presumption that realization is not probable.
Share-Based Compensation	(s) Share-Based Compensation The Company records as an expense in its financial statements the fair value of all equity-settled stock-based compensation awards. The terms and vesting schedules for share-based awards vary by type of grant. Generally, the awards vest subject to time- based conditions. Compensation expense is recognized ratably over the service period.
Critical Accounting Estimates	(t) Critical Accounting Estimates We prepare our consolidated financial statements in accordance with U.S. GAAP, which requires us to make estimates in the application of our accounting policies based on our best assumptions, judgments and opinions. On a regular basis, management reviews the accounting policies, assumptions, estimates and judgments to ensure that our consolidated financial statements are presented fairly and in accordance with U.S. GAAP. However, because future events and their effects cannot be determined with certainty, actual results could differ from our assumptions and estimates, and such differences could
Foreign Currency Transactions	(u) Foreign Currency Transactions Substantially all of the Company’s cash receipts are in U.S. Dollars. The Company’s disbursements, however, are in the currency invoiced by the supplier. The Company remits funds in the various currencies invoiced. The non-U.S. The primary source of our foreign exchange gains and losses are the movements on our Norwegian Kroner denominated 2018 Bonds. The 2018 Bonds are translated into U.S. Dollars at each reporting date at the prevailing exchange rate at the end of the period. The movement in the foreign exchange rates between each reporting date will result in a foreign exchange gain or loss on the 2018 Bonds, which is shown as a single line on the face of the statement of operations. The foreign currency exchange gain on the 2018 Bonds for the year ended December 31, 2021, was $2.1 million, compared to a foreign currency exchange loss of $1.9 million for the year ended December 31, 2020 , and a foreign currency exchange gain of $1.0 for the year ended December 31, 2019. The aggregate amount of all foreign exchange movements recorded in net income for the year ended December 31, 2021, was a $2.9 million gain compared to a $1.7 million loss for the year ended December 31, 2020, and a $0.8 million gain for the year ended December 31, 2019. The movement was primarily as a result of the foreign currency translation, at the prevailing exchange rate, of the 2018 Bonds mentioned in the previous paragraph.
Derivative instruments	(v) Derivative instruments Derivative instruments are initially recorded at fair value as either assets or liabilities in the accompanying balance sheets are subsequently remeasured to fair value at each reporting date, regardless of the purpose or intent for holding the derivative. The resulting derivative assets or liabilities are shown as a single line and are not netted off against one another on the face of the balance sheet. The method of recognizing the resulting gain or loss is dependent on whether the derivative contract qualifies for hedge accounting and has been designated as a hedging instrument. For derivative instruments that are not designated or that do not qualify as hedging instruments under ASC 815 – Derivatives and Hedging, the liability has been recognized as ‘Derivative liabilities’ on the balance sheet and changes in the fair value of the derivative financial instruments are recognized in earnings. Gains and losses from the Company’s non-designated non-designated
Income Taxes	(w) Income Taxes Navigator Holdings Ltd. and its Marshall Islands subsidiaries are currently not required to pay income taxes in the Marshall Islands on ordinary income or capital gains as they qualify as exempt companies. The Company has four wholly owned subsidiaries incorporated in the United Kingdom where the base tax rate is 19%. These subsidiaries provide services to affiliated entities within the group. The Company has a subsidiary in Poland where the base tax rate is 19%. The subsidiary earns management fees from fellow subsidiary companies. The Company The Company has a subsidiary in the United States of America where the base tax rate is currently 21%. The subsidiary owns a 50% interest in the Export Terminal Joint Venture, a pass through entity for U.S. tax purposes with the subsidiary liable for its share of the profits of the Marine Export Terminal. The Company has consolidated a VIE incorporated in Malta where the base tax rate is 35%. This VIE is the lessor entity for the sale and leaseback of Navigator Aurora The Company considered the income tax disclosure requirements of ASC 740 – Income Taxes, with regard to disclosing material unrecognized tax benefits; none were identified. The Company’s policy is to recognize accrued interest and penalties for unrecognized tax benefits as a component of tax expense. As of December 31, 2020, and 2021, there were no accrued interest and penalties for unrecognized tax benefits. Deferred taxation Deferred income tax assets and liabilities are recognized for the future tax consequences attributed to differences between the financial statements and tax basis of existing assets and liabilities using enacted rates applicable to the periods in which the differences are expected to affect taxable income. Deferred income tax balances included on the consolidated balance sheets reflect the effects of temporary differences between the carrying amounts of assets and liabilities and their tax basis and are stated at enacted tax rates expected to be in effect when taxes are actually paid or recovered. Deferred income tax assets represent amounts available to reduce income taxes payable on taxable income in future years. The recoverability of these future tax deductions is evaluated by assessing the adequacy of future taxable income, including the reversal of temporary differences and forecasted operating earnings. If it is deemed more likely than not that the deferred tax assets will not be realized, the Company provides for a valuation
Earnings Per Share	(x) Earnings Per Share Basic earnings per common share (“Basic EPS”) is computed by dividing the net income/(loss) available to common stockholders by the weighted average number of shares outstanding. Diluted earnings per common share (“Diluted EPS”) are computed by dividing the net income available to common stockholders by the weighted average number of common shares and dilutive common share equivalents then outstanding. Shares granted pursuant to the 2013 Restricted Stock Plan are the only dilutive shares, and these shares have been considered as outstanding since their respective grant dates for purposes of computing diluted earnings per share. These shares were antidilutive in the years ended December 31, 2019, 2020 and 2021 and thus not included in the calculation of diluted EPS in the last three years.
Related parties	(y) Related parties Parties are related if one party has the ability, directly or indirectly, to control the other party or exercise significant influence over the other party in making financial and operating decisions. Parties are also related if they are subject to common control or significant influence.
Segment Reporting	(z) Segment Reporting Management internally evaluates the performance of the enterprise as a whole and not on the basis of separate business units or different types of charters. As a result, the Company has determined that it operates as one reportable segment. Since the Company’s vessels regularly move between countries in international waters over many trade routes, it is impractical to assign revenues or earnings from the transportation of international LPG and petrochemical products by geographic area. Other than two vessels involved in cabotage trade within Indonesia for the years ended Decem b er 31, 2021 (December 31, 2020: three vessels), our vessels operate on a worldwide basis and are not restricted to specific locations. As disclosed in Note 6—Operating revenue to our consolidated financial statements, there are two different revenue streams due to the nature of the contracts that we operate. The Company considers the equity method investments do not meet the criteria in ASC 280 to be separate reportable segments.
Recent Accounting Pronouncements	(aa) Recent Accounting Pronouncements The following accounting standards issued as of April 2 8 In January 2021, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2021-01, pay-variable Accounting Standards Updates, recently adopted ASU 2016-13 In June 2016, FASB issued ASU 2016-13, held-to-maturity available-for-sale In May 2019, the FASB issued ASU No. 2019-05 In April 2019, the FASB issued ASU No. 2019-04, No. 2018-19, 326-20. 2019-04, In May 2019, the FASB issued ASU 2019-05, Financial Instruments—Credit Losses (Topic 326): Targeted Transition Relief which provides transition relief for entities adopting the credit losses standard, ASU 2016-13. Specifically, ASU 2019-05 amends ASU 2016-13 to allow companies to irrevocably elect, on adoption of ASU 2016-13, the fair value option for financial instruments that were previously recorded at amortized cost, are within the scope of the guidance in ASC 326-20, are eligible for the fair value option under ASC 825-20 and are not held-to-maturity debt securities. In May 2019, the FASB issued ASU 2019-11, 2019-11 2016-13. ASC 842 (Leases) On January 1, 2019, the Company adopted ASU 2016-02, on-balance 842-10-65-1(f) use-of-hindsight The lessor accounting under ASC 842 has not fundamentally changed from legacy US GAAP (Topic 840). Under new guidance lessees and lessor will disclosure key information about their leasing transactions. The Company’s management concludes that Unigas International B.V. (“Pool Manager”) is Principal in the Unigas Pool arrangement, and it has also identified that its contract regarding vessels contributed to the Unigas pool contain a lease in accordance with ASC 842
Vessels [Member]
Vessels	(b) Vessels Vessels are stated at cost, which includes the cost of construction, capitalized interest and other direct costs attributable to the construction. The cost of the vessels (excluding the estimated initial drydocking cost is or 2020
Vessels Under Construction [Member]
Vessels	(c) Vessels held for sale Assets are classified as held for sale when the Company commits to a plan to sell the asset, the sale is probable within one year, and the asset is available for immediate sale in its present condition. Consideration is given to whether the asset is currently being marketed for sale at a price that is reasonable in relation to its current fair value, and whether actions required to complete the plan indicate that it is unlikely that significant changes to the intention to sell will be made or that the intention to sell will be withdrawn. When assets are classified as held for sale, they are measured at the lower of their carrying amount or fair value less cost to sell and they are tested for impairment. A loss is recognized when the carrying value of the asset exceeds the estimated fair value, less transaction costs. Assets classified as held for sale are no longer depreciated. The net book value one of the vessels held for resale was impaired by $5.4 million as of December 31, 2021.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Summary of net income generated	The following table summarizes our net income generated from our participation in the Luna Pool for the years ended December 31, 2020 and 2021. Year ended Year ended (in thousands) Income / (expenses) Time and Voyage Charter Revenues $ 49,613 $ 90,592 Time and Voyage charter revenues from Luna Pool collaborative arrangements 12,830 26,555 Brokerage Commissions (804 ) (1,413 ) Voyage Expenses (14,966 ) (34,130 ) Voyage Expenses – Luna Pool collaborative arrangements (12,418 ) (20,913 ) Total net operating income from the Luna Pool 34,255 60,691 Other Income 199 367 Total net income from the Luna Pool $ 34,454 $ 61,058

Business Combinations (Tables)

Business Combinations (Tables)	12 Months Ended
	Dec. 31, 2021
Business Combinations [Abstract]
Summary of consideration transferred to acquire Ultragas and the assets acquired and liabilities	The following table summarizes the consideration transferred and the assets acquired and liabilities assumed as of the acquisition date. Amount Consideration Equity consideration $ 202,910 Fair value of consideration transferred $ 202,910 Net assets acquired: Handysize vessels 215,852 Smaller vessels 160,734 Cash and cash equivalents 17,477 Accounts receivable 7,071 Inventory 2,039 Other current assets 4,615 Equity method investments 2,580 Debt (192,695 ) Accounts payable (3,175 ) Accrued interest (1,602 ) Other current liabilities (3,982 ) Other long-term liabilities (6,004 ) Net assets acquired $ 202,910
Summary of proforma revenues and net income	The unaudited proforma financial information is based on Navigator Holdings Ltd’s and Ultragas’ historical consolidated financial statements as adjusted to give effect to the acquisition of Ultragas. The following unaudited revenue and net income/(loss) gives effect to the Ultragas Transaction as if it had occurred on January 1, 2020. Year ended Year ended (in thousands) Revenues of the combined entity $ 437,957 $ 470,373 Net income/(loss) of the combined entity 4,056 (23,816 )

Derivative Instruments Accoun_2

Derivative Instruments Accounted for at Fair Value (Tables)	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Schedule of Estimated Fair Value and Carrying Value of Assets and Liabilities Measured at Fair Value on Recurring Basis, Non-recurring Basis	The following table includes the estimated fair value of those assets and liabilities that are measured at fair value on a recurring basis as of December 31, 2020 and 2021. December 31, 2020 December 31, 2021 Fair Value Hierarchy Level Fair Fair Value Fair Value (in thousands) Cross-currency interest rate swap agreement Level 2 $ (2,896 ) $ (5,052 ) Interest rate swap agreements liabilities Level 2 (111 ) (3,748 ) Interest rate swap agreements assets Level 2 — 579

Fair Value of Financial Instr_2

Fair Value of Financial Instruments Not Accounted For at Fair Value (Tables)	12 Months Ended
	Dec. 31, 2021
Investments, All Other Investments [Abstract]
Schedule of Estimated Fair Value and Carrying Value of Assets and Liabilities Measured at Fair Value on Recurring Basis, Non-recurring Basis	The following table includes the estimated fair value and carrying value of those assets and liabilities where the fair value does not approximate to carrying value. The table excludes cash, cash equivalents and restricted cash, accounts receivable, accounts payable, accrued expenses and other liabilities because the fair value approximates carrying value and, for accounts receivable and payable, are due in one year or less. December 31, 2020 December 31, 2021 Fair Value Hierarchy Level Fair Carrying Fair Value Carrying Fair Value (in thousands) 2018 Bonds (note 12) Level 2 (70,299 ) (72,672 ) (68,154 ) (69,970 ) 2020 Bonds (note 13) Level 2 (100,000 ) (103,500 ) (100,000 ) (104,000 ) Secured term loan facilities and revolving credit facilities (note 11) Level 2 (685,930 ) (685,930 ) (815,942 ) (815,942 )

Operating Revenues (Tables)

Operating Revenues (Tables)	12 Months Ended
	Dec. 31, 2021
Revenue from Contract with Customer [Abstract]
Summary of Operating Revenue by Source of Revenue Stream	The following table compares our operating revenues by the source of revenue stream for the years ended December 31, 2019 Year ended 2019 2020 2021 (in thousands) Operating revenues: Time charters $ 168,641 $ 177,762 $ 190,420 Voyage charters 132,744 141,903 162,502 Time charters from Luna Pool collaborative arrangements — 606 1,283 Voyage charters from Luna Pool collaborative arrangements — 12,224 25,272 Operating revenues from Unigas Pool — — 27,004 Total operating revenues $ 301,385 $ 332,495 $ 406,481
Committed Time Charter Income	The estimated undiscounted cash flows for committed time charter revenue expected to be received on an annual basis for ongoing time charters, as of each December 31, is as follows: (in thousands) 2022: $ 121,571 2023: $ 77,541 2024: $ 61,319 2025: $ 61,174 2026: $ 34,539 2027 onwards: $ 5,347

Vessels, net (Tables)

Vessels, net (Tables)	12 Months Ended
	Dec. 31, 2021
Vessels	Vessel Drydocking Total Cost January 1, 2020 $ 2,060,280 $ 36,228 $ 2,096,508 Additions 2,233 10,192 12,425 Write-offs of fully amortized assets — (6,766 ) (6,766 ) December 31, 2020 2,062,513 39,654 2,102,167 Vessel additions on acquisition 363,951 12,635 376,586 Additions 3,150 19,946 23,096 Transfer to assets held for sale (55,877 ) (3,515 ) (59,392 ) Disposals (4,299 ) (451 ) (4,750 ) Write-offs of fully amortized assets — (12,691 ) (12,691 ) Vessel impairments (63,581 ) — (63,581 ) December 31, 2021 $ 2,305,857 $ 55,578 $ 2,361,435 Accumulated Depreciation January 1, 2020 $ 468,403 $ 18,578 $ 486,981 Charge for the period 68,033 8,231 76,264 Write-offs of fully amortized assets — (6,766 ) (6,766 ) December 31, 2020 536,436 20,043 556,479 Charge for the period 76,481 11,562 88,043 Transfer to assets held for sale (32,460 ) (988 ) (33,448 ) Disposals (100 ) (100 ) (200 ) Write-offs of fully amortized assets — (12,691 ) (12,691 ) December 31, 2021 $ 580,357 $ 17,826 $ 598,183 Net Book Value December 31, 2019 $ 1,591,877 $ 17,650 $ 1,609,527 December 31, 2020 $ 1,526,077 $ 19,611 $ 1,545,688 December 31, 2021 $ 1,725,500 $ 37,752 $ 1,763,252

Assets Held For Sale (Tables)

Assets Held For Sale (Tables)	12 Months Ended
	Dec. 31, 2021
Assets held for sale [Abstract]
Summary of Assets held for sale	2021 (in thousands) As of January 1 — Reclassification from Vessels 25,944 As of December 31 25,944

Equity Method Investments (Tabl

Equity Method Investments (Tables)	12 Months Ended
	Dec. 31, 2021
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Participation in Investments That Are Accounted For Using The Equity Method	As of December 31, 2020, and 2021, we had the following participation in investments that are accounted for using the equity method: December 31, December 31, 2020 2021 Enterprise Navigator Ethylene Terminal L.L.C. (“Export Terminal Joint Venture”) 50 % 50 % Luna Pool Agency Limited. (“Pool Agency”) 50 % 50 % Unigas International B.V. (“Unigas”) — 33.33 % Dan Unity CO2 A/S — 50 %
Schedule of Investments in Equity Accounted Joint Venture	The table below represents movement in the Company’s equity method investments, as of December 31, 2019, 2020, and 2021: 2019 2020 2021 (in thousands) Equity method investments at January 1 $ 42,462 $ 130,660 $ 148,665 Contributions to equity method investments 84,500 17,000 4,000 Equity method investments – additions — — 2,580 Share of results (1,126 ) 651 11,147 Distributions received from equity method investments — — (16,183 ) Capitalized interest and deferred financing costs 4,824 354 — Total equity method investments at December 31 $ 130,660 $ 148,665 $ 150,209

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	12 Months Ended
	Dec. 31, 2021
Variable Interest Entities Disclosure [Abstract]
Schedule of Assets and Liabilities of the Lessor VIE	The assets and liabilities of the lessor VIE that most significantly impact the Company’ consolidated balance sheets and the financial statement line items in which they are presented, as of December 31, 2020 and 2021, are as follows: December 31, December 31, 2020 2021 (in thousands) Assets Cash, cash equivalents and restricted cash $ 215 $ 124 Prepaid expenses and other current assets — 324 Liabilities Amounts due to related parties, current $ (229 ) (197 ) Amounts due to related parties, non-current (61,361 ) (54,767 ) $ (61,590 ) $ (54,964 )

Secured Term Loan Facilities _2

Secured Term Loan Facilities and Revolving Credit Facilities (Tables)	12 Months Ended
	Dec. 31, 2021
Schedule of Annual Principal Payments to Term Loans and Revolving Credit Facilities	The table below represents the annual principal payments to be made under our term loans and revolving credit facilities after December 31, 2020 and 2021: December 31, December 31, (in thousands) Due within one year $ 67,936 $ 151,586 Due in two years 124,479 229,460 Due in three years 202,353 209,633 Due in four years 175,413 92,381 Due in five years 54,388 50,403 Due in more than five years* 61,361 82,479 Total secured term loans and revolving credit facilities $ 685,930 $ 815,942 Less: current portion 67,936 151,586 Secured term loan facilities and revolving credit facility, non-current $ 617,994 $ 664,356 * Includes amounts relating to the Navigator Aurora Facility held within a lessor entity (for which legal ownership resides with financial institutions) that we are required to consolidate under U.S. GAAP into our financial statements as a variable interest entity (Please read Note 10—Variable Interest Entities to our consolidated financial statements)
Schedule of Breakdown of Secured Term Loan Facilities and Total Deferred Financing Costs Split Between Current and Non-Current Liabilities	The following table shows the breakdown of secured term loan facilities and total deferred financing costs split between current and non-current December 31, December 31, (in thousands) Current Liability Current portion of secured term loan facilities $ 67,936 $ 151,586 Less: current portion of deferred financing costs (2,274 ) (3,016 ) Current portion of secured term loan facilities, net of deferred financing costs $ 65,662 $ 148,570 Non-Current Secured term loan facilities and revolving credit facilities net of current portion* $ 617,994 $ 664,356 Less: non-current (4,183 ) (4,689 ) Non-current non-current $ 613,811 $ 659,667 * Includes amounts relating to the Navigator Aurora Facility held within a lessor entity (for which legal ownership resides with a financial institution) that we are required to consolidate under U.S. GAAP into our financial statements as a variable interest entity Please read Note 10—Variable Interest Entities to our consolidated financial statements.
Senior Secured Bonds [Member]
Schedule of Breakdown of Secured Term Loan Facilities and Total Deferred Financing Costs Split Between Current and Non-Current Liabilities	The following table shows the breakdown of our senior secured bond and total deferred financing costs as of December 31, 2020, and 2021: December 31, December 31, (in thousands) Senior Secured Bond Total Bond $ 70,299 $ 68,154 Less deferred financing costs (719 ) (466 ) Total Bond, net of deferred financing costs $ 69,580 $ 67,688
2020 Senior Unsecured Bonds [Member]
Schedule of Breakdown of Secured Term Loan Facilities and Total Deferred Financing Costs Split Between Current and Non-Current Liabilities	The following table shows the breakdown of our senior unsecured bonds and total deferred financing costs as of December 31, 2020 and 2021: December 31, December 31, (in thousands) Senior Unsecured Bonds Total 2020 Bonds $ 100,000 100,000 Less deferred financing costs (1,842 ) (1,449 ) Total Bonds, net of deferred financing costs $ 98,158 $ 98,551

Loss per Share (Tables)

Loss per Share (Tables)	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Calculation of Basic and Diluted Number of Weighted Average Outstanding Shares	The following table shows calculation of both basic and diluted number of weighted average outstanding shares for the years ended December 31, 2019, 2020 and 2021 December 31, December 31, December 31, Basic and diluted loss available to common stockholders of Navigator Holdings Ltd (in thousands) (16,706 ) (443 ) (30,964 ) Basic weighted average number of shares 55,792,711 55,885,376 64,669,567 Effect of dilutive potential share options*: — — — Diluted weighted average number of shares 55,792,711 55,885,376 64,669,567 * Due to a loss for the years ended December 31, 2019, 2020

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2021
Share-based Payment Arrangement [Abstract]
Restricted Share Grant Activity	Restricted share grant activity for the year ended December 31, 2020 and 2021 was as follows: Number of non-vested Weighted Weighted Balance as of January 1, 2020 329,156 $ 11.68 1.38 years Granted 79,172 7.90 Vested (89,888 ) 12.25 Forfeited (12,198 ) 11.54 Balance as of December 31, 2020 306,242 $ 10.54 0.93 years Granted 100,263 9.99 Vested (286,895 ) 10.66 Forfeited (16,123 ) 8.89 Balance as of December 31, 2021 103,487 $ 9.92 1.06 years
Summary of Stock Option Activity	The movements in the existing share options during the years ended December 31, 2020 2021 Options Number of Weighted Aggregate Balance as of January 1, 2020 349,936 $ 21.39 — Post vesting cancellations during the year (10,000 ) 20.82 — Balance as of December 31, 2020 339,936 21.40 $ — Post vesting cancellations during the year (29,080 ) 20.45 — Balance as of December 31, 2021 310,856 21.37 $ —

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Summary of Contractual Obligations	The contractual obligations schedule set forth below summarizes our contractual obligations as of December 31, 2021: 2022 2023 2024 2025 2026 Thereafter Total (in thousands) Secured term loan facilities and revolving credit facilities 151,586 229,460 209,633 92,380 50,403 27,602 761,064 2020 Bonds — — — 100,000 — — 100,000 2018 Bonds — 71,697 — — — — 71,697 Office operating leases 1 475 244 999 1,334 1,133 1,403 5,588 Navigator Aurora Facility 2 — — — — 54,767 — 54,767 Total contractual obligations $ 152,061 $ 301,401 $ 210,632 $ 193,714 $ 106,303 $ 29,005 $ 993,116 1 The Company occupies office space in London with a new lease commenced in January 2022 for a period of fifth The Company entered into a lease for office space in New York that now expires on May 31, 2022. The annual gross rent under this lease is approximately $0.4 million, subject to certain adjustments. The lease term for our representative office in Gdynia, Poland was revised during 2021 The Company occupies office space in Denmark with a lease commenced in September 2021 December 20 The weighted average remaining contractual lease term for the above four office leases on December 31, 2021 2 The Navigator Aurora Facility is a loan facility held within a lessor entity (for which legal ownership resides with financial institutions) that we are required to consolidate under U.S. GAAP into our financial statements as a variable interest entity. Please read Note 10—Variable Interest Entities to our consolidated financial statements.

Operating Lease Liabilities (Ta

Operating Lease Liabilities (Tables)	12 Months Ended
	Dec. 31, 2021
Operating Lease Liabilities [Abstract]
Maturity Analysis of The Undiscounted Cash Flows of The Company's Operating Lease Liabilities	A maturity analysis of the undiscounted cash flows of the Company’s operating lease liabilities as at December 31, 2020 2021 December 31, 2020 December 31, 2021 (in thousands) One year $ 1,572 $ 398 Two years 1,300 181 Three years 1,144 181 Four years 1,144 181 Five years 1,144 — Six years and thereafter 1,222 — Total undiscounted operating lease commitments $ 7,526 $ 941 Less: Discount adjustment (1,018 ) (38 ) Total operating lease liabilities $ 6,508 $ 903 Less: current portion (1,276 ) (381 ) Operating lease liabilities, non-current $ 5,232 $ 522

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Summary of Income Tax Reconciliation	However, the Company’s U.S, UK, Polish, Danish and Singaporean subsidiaries and Maltese VIE (please read Note 10—Variable Interest Entities to our consolidated financial statements) are subject to local taxes. 2019 2020 2021 (Loss)/income before income taxes and share of result of equity method investments $ (15,129 ) $ 1,279 $ (38,394 ) Tax expense at statutory rate — — — Total statutory tax charge — — — Tax charge in U.S. subsidiaries — — 855 Tax charge in UK subsidiaries 199 416 566 Tax (credit)/charge in Polish subsidiary (65 ) 31 345 Tax charge in Singapore subsidiary 213 77 47 Tax charge in Danish subsidiary — — 74 Tax charge in Maltese VIE (note 10) 5 93 82 Total tax charge $ 352 $ 617 $ 1,969 Breakdown of current/deferred tax expense Current tax expense 524 489 1,264 Deferred tax expense (172 ) 128 705 Total corporate income tax $ 352 $ 617 $ 1,969
Summary of Deferred Tax Assets and Liabilities	The tax effects of temporary differences that give rise to significant portions of the deferred tax assets and deferred tax liabilities as of December 31, 2020, and 2021 2020 2021 Deferred tax asset Net operating losses carry forwards $ 19,601 $ 21,592 Other temporary differences — 388 Total deferred tax assets 19,601 21,980 Less valuation allowance (1,731 ) — Deferred tax asset, net of valuation allowance 17,870 21,980 Deferred tax liabilities Investment in joint venture 17,449 21,871 Other temporary differences 32 517 Total deferred tax liabilities $ 17,481 $ 22,388 Net deferred tax asset/(liability) 389 (408 )

Cash, Cash Equivalents and Re_2

Cash, Cash Equivalents and Restricted Cash (Tables)	12 Months Ended
	Dec. 31, 2021
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract]
Schedule of breakdown of cash, cash equivalents and restricted cash	The following table shows the breakdown of cash, cash equivalents and restricted cash as of Dec December 31, December 31, (in thousands) Cash, Cash Equivalents and Restricted Cash Cash and cash equivalents $ 59,056 $ 123,886 Cash and cash equivalents held by VIE (note 10) 215 337 Total cash, cash equivalents and restricted cash $ 59,271 $ 124,223

Related Party Transactions (Tab

Related Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2021
Disclosure of Related Party Transactions [Line Items]
Schedule Of Related Party Transactions Income Expenses	The following table summarizes our transactions with related parties for the years ended December 31, 2020 and 2021: Year ended Year ended (in thousands) Net income / (expenses) Luna Pool Agency Limited $ — $ (30 ) Ocean Yield Malta Limited (1,827 ) (1,202 ) Ultranav Business Support ApS — (936 ) Naviera Ultranav Limitada — (25 ) Total $ (1,827 ) $ (2,193 )
Schedule of Related Party Transaction Due From Related Party	The following table sets out the balances due from related parties as at December 31, 2020 and 2021: December 31, December 31, (in thousands) Due from Related Parties Luna Pool Agency Limited $ 11,853 $ 8,450 Unigas Pool — 8,049 Dan Unity — 109 Naviera Ultranav Limitada — 128 Total $ 11,853 $ 16,736
Schedule of Related Party Transaction Due To Related Party	The following table sets out the balances due to related parties as at December 31, 2020 and 2021: December 31, 2020 December 31, 2021 (in thousands) Due to Related Parties Ocean Yield Malta Limited $ 61,448 $ 55,074 Naviera Ultranav Limitada — 27 Total $ 61,448 $ 55,101

Description of Business - Addit

Description of Business - Additional Information (Detail) MT in Millions	Aug. 31, 2021m³	Dec. 31, 2021MTm³
Schedule Of Description Of Business [Line Items]
Number of gas carriers owned & operated	17	55
Exporting capacity per year | MT		1
Equity ownership percentage		50.00%
Othello Shipping and Ultragas [Member]
Schedule Of Description Of Business [Line Items]
Equity ownership percentage	100.00%
Semi Refrigerated [Member]
Schedule Of Description Of Business [Line Items]
Number of gas carriers owned & operated		31
Ethylene [Member]
Schedule Of Description Of Business [Line Items]
Number of gas carriers owned & operated	8
Minimum [Member]
Schedule Of Description Of Business [Line Items]
Gas carrier cargo capacity	3,770	3,770
Maximum [Member]
Schedule Of Description Of Business [Line Items]
Gas carrier cargo capacity	22,000	38,000

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Aug. 31, 2021	Mar. 31, 2020
Summary Of Significant Accounting Policies [Line Items]
Impact On Net Income Loss		$ 300,000
Equity method investment, ownership percentage	50.00%
Collateral amount held with swap provider	$ 0	0
Share based compensation, vesting period	3 years
Foreign currency transaction gain (loss)	$ 2,900,000	1,700,000	$ 800,000
Impairment of Intangible Assets	0	0	0
Dan Unity [Member]
Summary Of Significant Accounting Policies [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired				50.00%
Unigas Pool [Member]
Summary Of Significant Accounting Policies [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired				33.30%
General and administrative costs [Member]
Summary Of Significant Accounting Policies [Line Items]
Impact On Net Income Loss		500,000
Interest Expense [Member]
Summary Of Significant Accounting Policies [Line Items]
Impact On Net Income Loss		800,000
2018 Bonds [Member]
Summary Of Significant Accounting Policies [Line Items]
Foreign currency exchange gain on senior secured bonds	$ 2,100,000	$ 1,900,000	$ 1,000,000
Two Thousand Twenty Bonds [Member]
Summary Of Significant Accounting Policies [Line Items]
Debt Instrument, Issuance Date	Sep. 30, 2020
Enterprise Navigator Ethylene Terminals L.L.C. [Member]
Summary Of Significant Accounting Policies [Line Items]
Equity method investment, ownership percentage	50.00%	50.00%
Greater Bay Co Ltd [Member]
Summary Of Significant Accounting Policies [Line Items]
Equity method investment, ownership percentage					50.00%
UNITED KINGDOM [Member]
Summary Of Significant Accounting Policies [Line Items]
Base Tax rate	19.00%
POLAND [Member]
Summary Of Significant Accounting Policies [Line Items]
Base Tax rate	19.00%
SINGAPORE [Member]
Summary Of Significant Accounting Policies [Line Items]
Base Tax rate	17.00%
MALTA [Member]
Summary Of Significant Accounting Policies [Line Items]
Base Tax rate	35.00%
UNITED STATES
Summary Of Significant Accounting Policies [Line Items]
Base Tax rate	21.00%
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Dry dock period	30 months
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Dry dock period	60 months
Export Terminal [Member] | UNITED STATES
Summary Of Significant Accounting Policies [Line Items]
Subsidiary or Equity Method Investee, Cumulative Percentage Ownership after All Transactions	50.00%
Vessel [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life of vessels	30 years
Asset Impairment Charges	$ 58,200,000
Impairment of long lived assets held for resale	$ 5,400,000
Vessel [Member] | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life of vessels	25 years
Vessel [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Useful life of vessels	30 years

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of Net Income Generated (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenue Derived From Participation In An Organization [Line Items]
Time and Voyage charter revenues from Luna Pool collaborative arrangements	$ 26,555	$ 12,830
Brokerage commissions	(4,802)	(5,095)	$ (4,938)
Voyage Expenses	71,953	63,372	55,310
Voyage Expenses – Luna Pool collaborative arrangements	20,913	12,418
Total net operating income from the Luna Pool	(2,951)	41,754	32,611
Other Income	367	199
(Loss)/income before income taxes and share of equity method investments	(38,394)	1,279	$ (15,129)
NVGS Luna Pool Agency Limited [Member]
Revenue Derived From Participation In An Organization [Line Items]
Brokerage commissions	(1,413)	(804)
Voyage Expenses	(34,130)	(14,966)
Voyage Expenses – Luna Pool collaborative arrangements	(20,913)	(12,418)
Total net operating income from the Luna Pool	60,691	34,255
Other Income	367	199
(Loss)/income before income taxes and share of equity method investments	61,058	34,454
NVGS Luna Pool Agency Limited [Member] | Time And Voyage And Charter Revenues [Member]
Revenue Derived From Participation In An Organization [Line Items]
Time and Voyage Charter Revenues	90,592	49,613
Time and Voyage charter revenues from Luna Pool collaborative arrangements	$ 26,555	$ 12,830

Business Combinations - Summar

Business Combinations - Summary of Consideration Transferred to Acquire Ultragas and the Assets Acquired and Liabilities (Detail) - Ultragas [Member] $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)
Consideration
Equity consideration	$ 202,910
Fair value of consideration transferred	202,910
Net assets acquired:
Cash and cash equivalents	17,477
Accounts receivable	7,071
Inventory	2,039
Other current assets	4,615
Equity method investments	2,580
Debt	(192,695)
Accounts payable	(3,175)
Accrued interest	(1,602)
Other current liabilities	(3,982)
Other long-term liabilities	(6,004)
Net assets acquired	202,910
Handysize vessels [Member]
Net assets acquired:
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets	215,852
Smaller vessels [Member]
Net assets acquired:
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets	$ 160,734

Business Combinations - Summ_2

Business Combinations - Summary of Proforma Revenues and Net Income (Detail) - Ultragas [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Revenues of the combined entity	$ 470,373	$ 437,957
Net income/(loss) of the combined entity	$ (23,816)	$ 4,056

Business Combinations - Additi

Business Combinations - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Aug. 04, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Business Acquisition, Transaction Costs		77,180,429	55,893,618
General and Administrative Expense		$ 28,881	$ 23,871	$ 20,878
Net Income		(30,964)	$ (443)	$ (16,706)
Unigas Intl B.V [Member]
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired	33.33%
Ultraship Crewing Philippines Inc [Member]
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired	25.00%
Ultraship Services Philippines Inc [Member]
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired	40.00%
Ultragas [Member]
Business Acquisition [Line Items]
General and Administrative Expense		1,300
Business Acquisition, Revenue Reported by Acquired Entity for Last Annual Period		52,500
Net Income		12,100
Equity consideration		$ 202,910
Ultranav [Member]
Business Acquisition [Line Items]
Total consideration	$ 410,400
Equity consideration	202,900
Debt and other liabilities assumed	$ 207,500
Ultranav [Member] | Common Stock [Member]
Business Acquisition [Line Items]
Business Acquisition, Transaction Costs	21,200,000
Business Acquisition, Share Price	$ 9.57

Derivative Instruments Accoun_3

Derivative Instruments Accounted for at Fair Value - Additional Information (Detail)	Jul. 02, 2020	Nov. 02, 2018USD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2021NOK (kr)	Dec. 31, 2018NOK (kr)	Nov. 02, 2018NOK (kr)
Derivative Instruments, Gain (Loss) [Line Items]
Derivatives designated as hedges held			$ 0	$ 0
Description of Interest Rate Derivative Activities	On July 2, 2020, the Company entered into floating-to-fixed interest rate swap agreements with ING Capital Markets LLC (“ING”) and Societe Generale (“SocGen”) with a termination date of December 31, 2025, to run concurrently with the Terminal Facility. Under these agreements, the notional amounts of the swaps are 80% of the amounts drawn under the Terminal Facility.
Unrealized Gain loss on Derivatives			791,000	2,762,000	$ (615,000)
Restricted Cash			0
Collateral amount held with swap provider			0	0
Derivative fair value of derivative asset amount offset against collateral			0
Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value of Derivative liability			5,100,000	2,900,000
Unrealized Gain loss on Derivatives			2,200,000	$ 2,900,000
2018 Senior Secured Bonds [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Outstanding secured borrowings, principal | kr						kr 600,000,000		kr 600,000,000
Outstanding secured borrowings			71,700,000
Outstanding secured borrowings, interest rate terms		The 2018 Bonds bear interest at a rate of 3-month NIBOR plus 6.0% per annum, calculated on a 360-day year basis and mature on November 2, 2023.
Debt Instrument, Description of Variable Rate Basis		The 2018 Bonds bear interest at a rate of 3-month NIBOR plus 6.0% per annum, calculated on a 360-day year basis and mature on November 2, 2023.
2018 Senior Secured Bonds [Member] | NORWAY
Derivative Instruments, Gain (Loss) [Line Items]
Outstanding secured borrowings, principal			$ 71,700,000
Outstanding secured borrowings | kr						kr 600,000,000
Spread on variable rate			6.608%	6.608%		6.608%
Outstanding secured borrowings, maturity year			2023
Outstanding secured borrowings, interest rate terms			6.608% plus 3-month U.S. LIBOR
Debt Instrument, Description of Variable Rate Basis			6.608% plus 3-month U.S. LIBOR
2018 Senior Secured Bonds [Member] | NORWAY | NIBOR [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Spread on variable rate			6.00%	6.00%		6.00%
Outstanding secured borrowings, interest rate terms			6.0% plus 3-month NIBOR
Debt Instrument, Description of Variable Rate Basis			6.0% plus 3-month NIBOR
Nordea Bank Abp [Member] | 2018 Senior Secured Bonds [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Outstanding secured borrowings, principal		$ 71,700,000					kr 600,000,000
Outstanding secured borrowings, interest rate terms		6.608% plus 3-month U.S. LIBOR
Debt Instrument, Description of Variable Rate Basis		6.608% plus 3-month U.S. LIBOR
Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value of Derivative liability				$ 100,000
Unrealized Gain loss on Derivatives			$ 2,800,000	$ 100,000
Outstanding secured borrowings, interest rate terms			3-month LIBOR, calculated on a 360-day year basis, which resets every three months in line with the dates of interest payments on the Terminal Facility.
Debt Instrument, Description of Variable Rate Basis			3-month LIBOR, calculated on a 360-day year basis, which resets every three months in line with the dates of interest payments on the Terminal Facility.
Fair value of Derivative asset			$ 3,200,000
Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Fair value of Derivative liability			500,000
Unrealized Gain loss on Derivatives			500,000
Interest Rate Swap [Member] | ING And SocGen [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized Gain loss on Derivatives			600,000
Fair value of Derivative			$ 70,000
Interest Rate Swap [Member] | Banco Santander Chile SA [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional Swaps Percentage			70.00%
Derivative, Fixed Interest Rate			1.627%			1.627%
Interest Rate Swap [Member] | Deutsche Bank AG London [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Notional Swaps Percentage			30.00%
Derivative, Fixed Interest Rate			2.137%			2.137%
Interest Rate Swap [Member] | Nordea Bank Abp [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Fixed Interest Rate			1.296%			1.296%
Interest Rate Swap [Member] | National Australia Bank Limited [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Fixed Interest Rate			1.296%			1.296%
Interest Rate Swap [Member] | ABN AMRO Bank N.V [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Fixed Interest Rate			1.296%			1.296%
Interest Rate Swap [Member] | BNP Paribas S.A. [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Fixed Interest Rate			1.296%			1.296%

Derivative Instruments Accoun_4

Derivative Instruments Accounted for at Fair Value - Schedule of Estimated Fair Value and Carrying Value of Assets and Liabilities Measured at Fair Value on Recurring Basis, Non-recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Cross Currency Interest Rate Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Asset (Liability)	$ (5,052)	$ (2,896)
Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Asset (Liability)	(3,748)	$ (111)
Derivative Asset	$ 579

Fair Value of Financial Instr_3

Fair Value of Financial Instruments Not Accounted For at Fair Value - Schedule of Estimated Fair Value and Carrying Value of Assets and Liabilities Measured at Fair Value on Recurring Basis, Non-recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Secured term loan facilities and revolving credit facility, Carrying Amount (Liability)	$ (815,942)	$ (685,930)
2018 Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Secured term loan facilities and revolving credit facility, Carrying Amount (Liability)	(71,697)
2020 Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Secured term loan facilities and revolving credit facility, Carrying Amount (Liability)	(100,000)
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior unsecured bond, Fair Value (Liability)	(69,970)	(72,672)
Secured term loan facilities and revolving credit facility, Fair Value (Liability)	(815,942)	(685,930)
Level 2 [Member] | 2018 Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Bonds, Carrying amount	(68,154)	(70,299)
Level 2 [Member] | 2020 Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior unsecured bond, Fair Value (Liability)	(104,000)	(103,500)
Long-term Debt, Gross	$ (100,000)	$ (100,000)

Operating Revenues - Summary of

Operating Revenues - Summary of Operating Revenue by Source of Revenue Stream (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating revenue
Operating revenue	$ 406,481	$ 332,495	$ 301,385
Unigas Pool [Member]
Operating revenue
Operating revenue	27,004
Time Charters [Member]
Operating revenue
Operating revenue	190,420	177,762	168,641
Time Charters [Member] | Luna Pool Agency Limited [Member]
Operating revenue
Operating revenue	1,283	606
Voyage Charters [Member]
Operating revenue
Operating revenue	162,502	141,903	$ 132,744
Voyage Charters [Member] | Luna Pool Agency Limited [Member]
Operating revenue
Operating revenue	$ 25,272	$ 12,224

Operating Revenues - Summary _2

Operating Revenues - Summary of Time Charter Revenues (Detail) - Time Charter [Member] $ in Thousands	Dec. 31, 2021USD ($)
Concentration Risk [Line Items]
2022:	$ 121,571
2023:	77,541
2024:	61,319
2025:	61,174
2026:	34,539
2027 Onwards:	$ 5,347

Operating Revenues - Additiona

Operating Revenues - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Deferred income	$ 18,510	$ 11,604
Revenue, performance obligation, description of timing	the Company’s 45 operated vessels, were subject to time charters, 19 of which will expire within one year, two of which will expire within three years, and five which will expire after more than five years from the balance sheet date.	the Company’s 38 operated vessels, were subject to time charters, 11 of which will expire within one year, six which will expire within three years, and two of which will expire after more than five years from the balance sheet date
Accounts Receivable Net	$ 31,906	$ 14,451
Accounting Standards Update 2014-09 [Member]
Contract Assets	4,500	8,400
Contracts Of Affreightment [Member]
Deferred income	1,300	11,400
Accounts Receivable Net	4,200	3,300
Voyage Charters [Member]
Deferred income	1,500	1,600
Accounts Receivable Net	3,300	11,100
Cargo Commences [Member]
Contract Costs Incurred In Advance	600	1,500
Cargo Commences [Member] | Accounting Standards Update 2014-09 [Member]
Deferred income	$ 17,000	$ 10,000

Vessels, net - Vessels (Detail)

Vessels, net - Vessels (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Vessel impairments	$ (63,581)
Net Book Value, ending balance	330	$ 502
Vessels [Member]
Property, Plant and Equipment [Line Items]
beginning balance	2,102,167	2,096,508
Vessel additions on acquisition	376,586
Additions	23,096	12,425
Transfer to assets held for sale	(59,392)
Disposal	(4,750)
Write-offs of fully amortized assets	(12,691)	(6,766)
Vessel impairments	(63,581)
ending balance	2,361,435	2,102,167
beginning balance	556,479	486,981
Charge for the period	88,043	76,264
Transfer to assets held for sale	(33,448)
Disposals for the period	(200)
Write-offs of fully amortized assets	(12,691)	(6,766)
ending balance	598,183	556,479
Net Book Value, ending balance	1,763,252	1,545,688	$ 1,609,527
Vessels [Member] | Vessel [Member]
Property, Plant and Equipment [Line Items]
beginning balance	2,062,513	2,060,280
Vessel additions on acquisition	363,951
Additions	3,150	2,233
Transfer to assets held for sale	(55,877)
Disposal	(4,299)
Vessel impairments	(63,581)
ending balance	2,305,857	2,062,513
beginning balance	536,436	468,403
Charge for the period	76,481	68,033
Transfer to assets held for sale	(32,460)
Disposals for the period	(100)
ending balance	580,357	536,436
Net Book Value, ending balance	1,725,500	1,526,077	1,591,877
Vessels [Member] | Drydocking [Member]
Property, Plant and Equipment [Line Items]
beginning balance	39,654	36,228
Vessel additions on acquisition	12,635
Additions	19,946	10,192
Transfer to assets held for sale	(3,515)
Disposal	(451)
Write-offs of fully amortized assets	(12,691)	(6,766)
ending balance	55,578	39,654
beginning balance	20,043	18,578
Charge for the period	11,562	8,231
Transfer to assets held for sale	(988)
Disposals for the period	(100)
Write-offs of fully amortized assets	(12,691)	(6,766)
ending balance	17,826	20,043
Net Book Value, ending balance	$ 37,752	$ 19,611	$ 17,650

Vessels, net - Additional Infor

Vessels, net - Additional Information (Detail)	Dec. 31, 2021USD ($)Vessels	Dec. 31, 2020USD ($)Vessels
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	$ 330,000	$ 502,000
Variable Interest Entities [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, cost	83,600,000	82,900,000
Property, plant and equipment, net	69,600,000	71,000,000
Time Charter Agreements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, cost	1,417,100	1,084,000,000
Property, plant and equipment, net	$ 1,046,400,000	$ 839,000,000
Number of vessels contracted | Vessels	26	19
Collateralized Loan Obligations [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, net	$ 1,576,800,000	$ 1,359,000,000

Assets held for sale - Long Li

Assets held for sale - Long Lived Assets Held For Sale (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)
Assets held for sale [Abstract]
Assets Held For Sale Reclassification From Property Plant And Equipment	$ 25,944
As of December 31	$ 25,944

Assets held for sale - Addition

Assets held for sale - Additional Information (Details)	12 Months Ended
	Dec. 31, 2021
Vessels In Operation [Member]
Assets Held For Sale [Line Items]
Long Lived Assets Held-for-sale, Description	assets held for sale comprised of two vessels, Navigator Neptune and Happy Bird, both of which were committed for sale to a non-related third party

Equity Method Investments - Sch

Equity Method Investments - Schedule of Participation in Investments That Are Accounted For Using The Equity Method (Detail)	Dec. 31, 2021	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	50.00%
Enterprise Navigator Ethylene Terminals L.L.C. [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	50.00%	50.00%
Luna Pool Agency Limited [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	50.00%	50.00%
Unigas International B V [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	33.33%
Dan Unity COTwo A S [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	50.00%

Equity Method Investments - Sum

Equity Method Investments - Summary of Investment in Equity Accounted Joint Venture (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule of Equity Method Investments Joint Ventures [Line Items]
Equity method investments , beginning balance	$ 148,665	$ 130,660	$ 42,462
Contributions to equity method investments	4,000	17,000	84,500
Equity Method Investment Additions	2,580
Share of results	11,147	651	(1,126)
Distributions received from equity method investments	(16,183)
Capitalized interest and deferred financing costs		354	4,824
Total Equity method investments , ending balance	$ 150,209	$ 148,665	$ 130,660

Equity Method Investments - Add

Equity Method Investments - Additional Information (Detail) - USD ($)	Jan. 21, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity		$ 6,100,000	$ 6,500,000
Amortization cost			300,000	$ 0
Share of results		$ 11,147,000	651,000	(1,126,000)
Economic interest in building and operating marine export terminal		50.00%
Unigas International B V [Member]
Schedule of Equity Method Investments [Line Items]
Economic interest in building and operating marine export terminal		33.33%
Equity Method Investment, Description of Principal Activities		commercial and operational manager of seagoing vessels capable of carrying liquefied petrochemical and petroleum gases on a worldwide basis.
Dan Unity COTwo A S [Member]
Schedule of Equity Method Investments [Line Items]
Economic interest in building and operating marine export terminal		50.00%
Equity Method Investment, Description of Principal Activities		commercial and technical projects relating to seaborne transportation of CO2.
Ethylene Marine Export Terminal [Member]
Schedule of Equity Method Investments [Line Items]
Capital contribution to joint ventures	$ 4,000,000
Amortization cost		$ 400,000
Export Terminal [Member]
Schedule of Equity Method Investments [Line Items]
Equity contributions to joint venture			146,500,000
Share of results		$ 11,400,000	$ 900,000	$ 1,100,000

Variable Interest Entities - Sc

Variable Interest Entities - Schedule of Assets and Liabilities of the Lessor VIE (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets
Prepaid expenses and other current assets	$ 16,293	$ 22,015
Liabilities
Amounts due to related parties, current	(224)	(229)
Amounts due to related parties, non-current	(54,877)	(61,219)
Due to Related Parties	(55,101)	(61,448)
Variable Interest Entity, Primary Beneficiary [Member]
Assets
Cash, cash equivalents and restricted cash	124	215
Prepaid expenses and other current assets	324	0
Liabilities
Amounts due to related parties, current	(197)	(229)
Amounts due to related parties, non-current	(54,767)	(61,361)
Due to Related Parties	$ (54,964)	$ (61,590)

Variable Interest Entities - Ad

Variable Interest Entities - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Aug. 04, 2021
Line of Credit Facility [Line Items]
Variable interest entity, consolidated, carrying amount, assets	$ 2,157,425	$ 1,839,408
Variable interest entity, consolidated, carrying amount, liabilities	1,039,971	897,013
Interest Expense	$ 38,682	41,080	$ 48,611
Proceeds from Related Party Debt			$ 69,052
Equity method investment, ownership percentage	50.00%
Leases	$ 44,800
Ultraship Crewing Philippines Inc [Member]
Line of Credit Facility [Line Items]
Equity method investment, ownership percentage				25.00%
Ultraship Services Philippines Inc. [Member]
Line of Credit Facility [Line Items]
Equity method investment, ownership percentage				40.00%
Common Stock [Member]
Line of Credit Facility [Line Items]
Variable Interest Entity, consolidated			49.00%
Ocean Yield Arora Ltd [Member]
Line of Credit Facility [Line Items]
Variable interest entity, consolidated, carrying amount, assets	58,900	63,500
Variable interest entity, consolidated, carrying amount, liabilities	55,500	61,700
Variable Interest Entity, Primary Beneficiary [Member]
Line of Credit Facility [Line Items]
Variable interest entity, consolidated, carrying amount, assets	139,100	125,900
Variable interest entity, consolidated, carrying amount, liabilities	18,500	9,500
Interest Expense	1,200	1,800
Proceeds from Related Party Debt	6,300	6,800
Variable Interest Entity, Primary Beneficiary [Member] | PT Navigator Khatulistiwa [Member]
Line of Credit Facility [Line Items]
Variable interest entity, consolidated, carrying amount, assets	198,500	189,400
Variable interest entity, consolidated, carrying amount, liabilities	$ 74,200	$ 71,200
Variable Interest Entity, consolidated	100.00%	100.00%

Secured Term Loan Facilities _3

Secured Term Loan Facilities and Revolving Credit Facilities - Schedule of Annual Principal Payments to Term Loans and Revolving Credit Facilities (Detail) - USD ($) $ in Thousands		Dec. 31, 2021	Dec. 31, 2020
Maturities of Long-term Debt [Abstract]
Due within one year		$ 151,586	$ 67,936
Due in two years		229,460	124,479
Due in three years		209,633	202,353
Due in four years		92,381	175,413
Due in five years		50,403	54,388
Due in more than five years	[1]	82,479	61,361
Total		815,942	685,930
Less: current portion		151,586	67,936
Secured term loan facilities and revolving credit facility, non-current portion	[1],[2]	$ 664,356	$ 617,994
[1]	Includes amounts relating to the Navigator Aurora Facility held within a lessor entity (for which legal ownership resides with financial institutions) that we are required to consolidate under U.S. GAAP into our financial statements as a variable interest entity (Please read Note 10—Variable Interest Entities to our consolidated financial statements)
[2]	Includes amounts relating to the Navigator Aurora Facility held within a lessor entity (for which legal ownership resides with a financial institution) that we are required to consolidate under U.S. GAAP into our financial statements as a variable interest entity Please read Note 10—Variable Interest Entities to our consolidated financial statements.

Secured Term Loan Facilities _4

Secured Term Loan Facilities and Revolving Credit Facilities - Additional Information (Detail)

Dec. 31, 2021USD ($)

Aug. 02, 2021USD ($)Year

Sep. 17, 2020USD ($)

Mar. 28, 2019USD ($)

Mar. 25, 2019USD ($)

Oct. 28, 2016USD ($)

Jul. 31, 2015USD ($)

Jan. 27, 2015USD ($)

Oct. 30, 2013USD ($)

Oct. 25, 2013USD ($)

Oct. 31, 2019USD ($)

Dec. 31, 2020USD ($)

Jun. 30, 2020USD ($)

Dec. 31, 2021USD ($)Repayments

Dec. 31, 2020USD ($)

Jun. 30, 2019

Jun. 30, 2017USD ($)

Dec. 31, 2015USD ($)

Debt Instrument [Line Items]

Debt instrument covenant description

financial covenants (each as defined within the bond agreement governing the 2020 Bonds (the “2020 Bond Agreement”)) are: (a) The issuer shall ensure that the Group (meaning “the Company and its subsidiaries”) maintains a minimum liquidity of no less than $35.0 million; and (b) maintain a Group equity ratio (as defined in the 2020 Bond Agreement) of at least 30%. As of December 31, 2021, the Company was in compliance with all covenants for the 2020 Bonds.

The 2020 Bond Agreement provides that we may declare or pay dividends to shareholders provided that the Company maintains a minimum liquidity of $60.0 million unless an event of default has occurred and is continuing. The 2020 Bond Agreement also limits us and our subsidiaries from, among other things, entering into mergers and divestitures, engaging in transactions with affiliates or incurring any additional liens which would have a material adverse effect. In addition, the 2020 Bond Agreement includes customary events of default, including those relating to a failure to pay principal or interest, a breach of covenant, false representation and warranty, a cross-default to other indebtedness, the occurrence of a material adverse effect, or our insolvency or dissolution.

Commitment fee on credit facility

0.91%

Unamortized Deferred costs

$ 2,000,000

$ 2,000,000

Line of credit facility ,expiration date

Apr. 30, 2027

Cash and cash equivalent carrying value

$ 123,886,000

59,056,000

$ 123,886,000

59,056,000

Gain loss on extinguishment of debt

500,000

Atlanticgas and Balearicgas [Member]

Debt Instrument [Line Items]

Debt Instrument, Term

12 years

Adriaticgas Celticgas and Happy Albatross [Member]

Debt Instrument [Line Items]

Debt Instrument, Term

12 years

Line of credit facility maximum borrowing capacity

$ 81,000,000

Line of credit facility ,expiration date

May 31, 2027

Beringgas and Pacificgas [Member]

Debt Instrument [Line Items]

Line of credit facility ,expiration date

Dec. 31, 2028

Ethylene Marine Export Terminal [Member]

Debt Instrument [Line Items]

Credit facility, amount outstanding

500,000

$ 500,000

Terminal Facility [Member]

Debt Instrument [Line Items]

Description Of Debt Modification Conditions

Under the Terminal Facility, the Marine Terminal Borrower must maintain a minimum debt service coverage ratio (as defined in the Terminal Facility) for the prior four calendar fiscal quarters (or shorter period of time if data for the prior four fiscal quarters is not available) of no less than 1.10 to 1.00.

Debt instrument variable rate description

plus 275 to 300 basis points

Line Of Credit Repayment Commencing Period

Mar. 31, 2021

Debt Instrument Covenant Description For Dividends Payments

the Marine Terminal Borrower can only pay dividends if the Marine Terminal Borrower satisfies certain customary conditions to paying a dividend, including maintaining a debt service coverage ratio for the immediately preceding four consecutive fiscal quarters and the projected immediately succeeding four consecutive fiscal quarters of not less than 1.20 to 1.00 and no default or event of default has occurred or is continuing

Terminal Facility [Member] | ING Capital LLC And SG America Securities [Member] | Ethylene Marine Export Terminal [Member]

Debt Instrument [Line Items]

Date of commencement of the terminal credit facility

Mar. 29, 2019

Line of credit facility maximum borrowing capacity

75,000,000

75,000,000

Terminal Facility [Member] | ING Capital LLC And SG America Securities [Member] | Ethylene Marine Export Terminal [Member] | Maturity Of Debt Time Two [Member]

Debt Instrument [Line Items]

Line of credit facility ,expiration date

Dec. 31, 2025

DB Credit Facility A [Member] | Atlanticgas and Balearicgas [Member]

Debt Instrument [Line Items]

Minimum Coverage Ratio Of Earnings Before Interest Taxes Depreciation And Amortization To Interest Expense

30.00%

Line of credit facility maximum borrowing capacity

$ 57,700,000

Line of credit outstanding amount

25,200,000

Line of credit facility periodic payment

$ 1,200,000

Debt instrumentvariable rate

205.00%

Cash and cash equivalent carrying value

$ 50,000,000

Percentage Of Senior Secured Loan Owed

5.00%

Collateral Requirements Percentage

125.00%

Santander Credit Facility A [Member] | Adriaticgas Celticgas and Happy Albatross [Member]

Debt Instrument [Line Items]

Line of credit outstanding amount

$ 37,100,000

Line of credit facility periodic payment

$ 1,200,000

Debt instrumentvariable rate

205.00%

Collateral Requirements Percentage

125.00%

Santander Credit Facility A [Member] | Quarterly Installment Three [Member] | Adriaticgas Celticgas and Happy Albatross [Member]

Debt Instrument [Line Items]

Line of credit facility periodic payment

$ 1,000,000

Santander Credit Facility B [Member]

Debt Instrument [Line Items]

Line of credit facility ,expiration date

Jan. 31, 2029

Santander Credit Facility B [Member] | Arcticgas and Happy Avocet [Member]

Debt Instrument [Line Items]

Debt Instrument, Term

12 years

Minimum Coverage Ratio Of Earnings Before Interest Taxes Depreciation And Amortization To Interest Expense

30.00%

Line of credit facility maximum borrowing capacity

$ 55,800,000

Line of credit outstanding amount

34,900,000

Line of credit facility periodic payment

$ 1,300,000

Debt instrumentvariable rate

205.00%

Cash and cash equivalent carrying value

$ 50,000,000

Percentage Of Senior Secured Loan Owed

5.00%

Collateral Requirements Percentage

125.00%

Santander Credit Facility B [Member] | Quarterly Installment Three [Member] | Arcticgas and Happy Avocet [Member]

Debt Instrument [Line Items]

Line of credit facility periodic payment

$ 1,100,000

DB Credit Facility B [Member] | Beringgas and Pacificgas [Member]

Debt Instrument [Line Items]

Debt Instrument, Term

12 years

Minimum Coverage Ratio Of Earnings Before Interest Taxes Depreciation And Amortization To Interest Expense

30.00%

Line of credit facility maximum borrowing capacity

$ 60,900,000

Line of credit outstanding amount

36,800,000

Line of credit facility periodic payment

$ 1,300,000

Debt instrumentvariable rate

205.00%

Cash and cash equivalent carrying value

$ 50,000,000

Percentage Of Senior Secured Loan Owed

5.00%

Collateral Requirements Percentage

125.00%

Minimum [Member] | Terminal Facility [Member]

Debt Instrument [Line Items]

Credit facility, final payment

3,400,000

Debt instrumentvariable rate

275.00%

Maximum [Member] | Terminal Facility [Member]

Debt Instrument [Line Items]

Credit facility, final payment

3,800,000

Debt instrumentvariable rate

300.00%

April 2013 Loan Facility [Member]

Debt Instrument [Line Items]

Credit facility, refinancing

$ 120,000,000

January 2015 Secured Term Loan Facility [Member]

Debt Instrument [Line Items]

Debt Instrument, Term

7 years

7 years

Credit facility, amount outstanding

88,400,000

88,400,000

Line of credit facility maximum borrowing capacity

$ 278,100,000

January 2015 Secured Term Loan Facility [Member] | Minimum [Member]

Debt Instrument [Line Items]

Credit facility, final payment

15,600,000

Line of credit facility periodic payment

500,000

Collateral Requirements Percentage

135.00%

January 2015 Secured Term Loan Facility [Member] | Maximum [Member]

Debt Instrument [Line Items]

Credit facility, final payment

18,300,000

Line of credit facility periodic payment

600,000

December 2015 Secured Revolving Credit Facility [Member]

Debt Instrument [Line Items]

Line of credit facility maximum borrowing capacity

$ 290,000,000

October 2016 Secured Revolving Credit Facility [Member]

Debt Instrument [Line Items]

Credit facility, expiring period

2023-11

Line of credit facility maximum borrowing capacity

$ 220,000,000

Line of credit outstanding amount

$ 78,400,000

Debt instrument number of periodic payments | Repayments

7

October 2016 Secured Revolving Credit Facility [Member] | Quarterly Installment One [Member]

Debt Instrument [Line Items]

Line of credit facility periodic payment

$ 4,100,000

October 2016 Secured Revolving Credit Facility [Member] | Quarterly Installment Three [Member]

Debt Instrument [Line Items]

Line of credit facility periodic payment

50,000,000

October 2016 Secured Revolving Credit Facility [Member] | Revolving Credit Facility [Member]

Debt Instrument [Line Items]

Credit facility, amount outstanding

20,000,000

20,000,000

October 2016 Secured Revolving Credit Facility [Member] | Minimum [Member]

Debt Instrument [Line Items]

Collateral Requirements Percentage

125.00%

June 2017 Secured Term Loan Facility [Member] | Navigator Gas L.L.C. [Member]

Debt Instrument [Line Items]

Line of credit facility maximum borrowing capacity

100,000,000

100,000,000

Line of credit outstanding amount

86,600,000

Line of credit facility periodic payment

4,100,000

Cash and cash equivalent carrying value

65,900,000

65,900,000

June 2017 Secured Term Loan and Revolving Credit Facility [Member] | Navigator Gas L.L.C. [Member]

Debt Instrument [Line Items]

Line of credit facility maximum borrowing capacity

$ 160,800,000

$ 160,800,000

$ 160,800,000

June 2017 Secured Term Loan and Revolving Credit Facility [Member] | Minimum [Member] | Navigator Gas L.L.C. [Member]

Debt Instrument [Line Items]

Cash required as percent of indebtedness

5.00%

Total equity to total assets

30.00%

30.00%

Minimum Coverage Ratio Of Earnings Before Interest Taxes Depreciation And Amortization To Interest Expense

0.91%

Cash and cash equivalent carrying value

$ 25,000

$ 25,000

Collateral Requirements Percentage

125.00%

June 2017 Revolving Credit Facility [Member] | Navigator Gas L.L.C. [Member]

Debt Instrument [Line Items]

Line of credit facility maximum borrowing capacity

60,800,000

$ 60,800,000

March 2019 Terminal Credit Agreement [Member]

Debt Instrument [Line Items]

Credit facility, amount outstanding

81,800,000

81,800,000

Credit facility, expiring period

2025-03

Line of credit facility periodic payment

$ 2,300,000

March 2019 Secured Term Loan [Member

Debt Instrument [Line Items]

Debt instrument covenant description

an amount equal to or greater than (i) $35.0 million, or (ii) 5% of Net Debt or total debt, as applicable; and the aggregate fair market value of the collateral vessels must be no less than 130% of the aggregate outstanding borrowing under the facility. As of December 31, 2021, the Company was in compliance with all covenants contained in this credit facility.

Final Payment Payable

54,400,000

$ 54,400,000

Proceeds from Issuance of Long-term Debt

$ 107,000,000

Line of credit facility maximum borrowing capacity

$ 107,000,000

Navigator Aurora Facility [Member]

Debt Instrument [Line Items]

Debt Instrument, Term

7 years

Unsecured Debt

54,800,000

$ 61,300,000

$ 54,800,000

61,300,000

Appraisal value of borrowings outstanding

20,800,000

$ 14,000,000

Line of credit facility maximum borrowing capacity

$ 69,100,000

Debt instrumentvariable rate

185.00%

September 2020 Secured Revolving Credit Facility [Member]

Debt Instrument [Line Items]

Credit facility, final payment

$ 185,000,000

$ 7,400,000

Debt instrument covenant description

The financial covenants each as defined within the credit facility are: a) the maintenance at all times of cash and cash equivalents in an amount equal to or greater than (i) $35.0 million, or (ii) 5% of total indebtedness (as defined by the September 2020 Secured Revolving Credit Facility agreement), as applicable; b) the maintenance of the ratio of total stockholders’ equity to total assets (both as defined by the September 2020 Secured Revolving Credit Facility agreement) of not less than 30% and the aggregate fair market value of the collateral vessels must be no less than 125% of the aggregate outstanding borrowing under the facility. Interest on amounts drawn is payable at a rate of U.S. LIBOR plus 250 basis points per annum. As of December 31, 2021, the Company was in compliance with all covenants contained in this revolving credit facility.

Credit facility, expiring period

2024-09

Description Of Line Of Credit Maturity And Extended Maturity

The facility is due to mature in September 2024, but contains an option, subject to the consent of the Lenders, exercisable 12 to 36 months after the date of the agreement, to extend the maturity date of the facility by 12 months to September 2025.

Final Ballon Payment Of Line Of Credit

$ 150,900,000

$ 2,800,000

Line Of Credit Facility Extended Expiration Date

2025-09

Line of credit facility maximum borrowing capacity

$ 210,000,000

Line of credit outstanding amount

$ 210,000,000

Collateral Requirements Percentage

125.00%

2019 Senior Secured Term Loan Facility [Member] | August 2021 Amendment and Restatement Agreement [Member]

Debt Instrument [Line Items]

Line of credit facility maximum borrowing capacity

$ 66,950,000

Line of credit facility ,expiration date

Aug. 2, 2021

Line of credit outstanding amount

$ 52,400,000

Debt instrument number of periodic payments | Year

9

Debt instrumentvariable rate

190.00%

Cash and cash equivalent carrying value

$ 50,000,000

Percentage Of Senior Secured Loan Owed

5.00%

Collateral Requirements Percentage

135.00%

2019 Senior Secured Term Loan Facility [Member] | Quarterly Installment One [Member] | August 2021 Amendment and Restatement Agreement [Member]

Debt Instrument [Line Items]

Line of credit facility periodic payment

$ 26,200,000

2019 Senior Secured Term Loan Facility [Member] | Quarterly Installment Three [Member] | August 2021 Amendment and Restatement Agreement [Member]

Debt Instrument [Line Items]

Line of credit facility periodic payment

$ 2,900,000

2019 Senior Secured Term Loan Facility [Member] | Minimum [Member] | London Interbank Offered Rate (LIBOR) [Member] | August 2021 Amendment and Restatement Agreement [Member]

Debt Instrument [Line Items]

Senior Secured Loan Basis Spread

1.873%

2019 Senior Secured Term Loan Facility [Member] | Maximum [Member] | London Interbank Offered Rate (LIBOR) [Member] | August 2021 Amendment and Restatement Agreement [Member]

Debt Instrument [Line Items]

Senior Secured Loan Basis Spread

1.88%

Secured Term Loan Facilities _5

Secured Term Loan Facilities and Revolving Credit Facilities - Schedule of Breakdown of Secured Term Loan Facilities and Total Deferred Financing Costs Split Between Current and Non-Current Liabilities (Detail) - USD ($) $ in Thousands		Dec. 31, 2021	Dec. 31, 2020
Current Liability
Current portion of secured term loan facilities		$ 151,586	$ 67,936
Less: current portion of deferred financing costs		(3,016)	(2,274)
Current portion of secured term loan facilities, net of deferred financing costs		148,570	65,662
Non-Current Liability
Secured term loan facilities and revolving credit facilities net of current portion	[1],[2]	664,356	617,994
Less: non-current portion of deferred financing costs	[1]	(4,689)	(4,183)
Non-current secured term loan facilities and revolving credit facilities, net of current portion and non-current deferred financing costs		$ 659,667	$ 613,811
[1]	Includes amounts relating to the Navigator Aurora Facility held within a lessor entity (for which legal ownership resides with a financial institution) that we are required to consolidate under U.S. GAAP into our financial statements as a variable interest entity Please read Note 10—Variable Interest Entities to our consolidated financial statements.
[2]	Includes amounts relating to the Navigator Aurora Facility held within a lessor entity (for which legal ownership resides with financial institutions) that we are required to consolidate under U.S. GAAP into our financial statements as a variable interest entity (Please read Note 10—Variable Interest Entities to our consolidated financial statements)

Senior Secured Bond - Additiona

Senior Secured Bond - Additional Information (Detail)	Nov. 02, 2018NOK (kr)	Dec. 31, 2020USD ($)	Dec. 31, 2021NOK (kr)	Dec. 31, 2021USD ($)	Dec. 31, 2018NOK (kr)	Nov. 02, 2018USD ($)
Debt Instrument [Line Items]
Interest payment description on bond	Interest is payable quarterly in arrears on February 2, May 2, August 2 and November 2.
Minimum liquidity to be maintained, amount		$ 59,056,000		$ 123,886,000
Debt instrument covenant description		financial covenants (each as defined within the bond agreement governing the 2020 Bonds (the “2020 Bond Agreement”)) are: (a) The issuer shall ensure that the Group (meaning “the Company and its subsidiaries”) maintains a minimum liquidity of no less than $35.0 million; and (b) maintain a Group equity ratio (as defined in the 2020 Bond Agreement) of at least 30%. As of December 31, 2021, the Company was in compliance with all covenants for the 2020 Bonds.	The 2020 Bond Agreement provides that we may declare or pay dividends to shareholders provided that the Company maintains a minimum liquidity of $60.0 million unless an event of default has occurred and is continuing. The 2020 Bond Agreement also limits us and our subsidiaries from, among other things, entering into mergers and divestitures, engaging in transactions with affiliates or incurring any additional liens which would have a material adverse effect. In addition, the 2020 Bond Agreement includes customary events of default, including those relating to a failure to pay principal or interest, a breach of covenant, false representation and warranty, a cross-default to other indebtedness, the occurrence of a material adverse effect, or our insolvency or dissolution.
2018 Senior Secured Bonds [Member]
Debt Instrument [Line Items]
Aggregate principal amount | kr	kr 600,000,000		kr 600,000,000
Variable interest rate on bond	6.00%
Debt instrument maturity date	Nov. 2, 2023
Debt instrument variable rate description	The 2018 Bonds bear interest at a rate of 3-month NIBOR plus 6.0% per annum, calculated on a 360-day year basis and mature on November 2, 2023.
Debt instrument redemption description	The Company may redeem the 2018 Bonds, in whole or in part, at any time. Any 2018 Bonds redeemed until November 1, 2022, are redeemable at 102.864% of par, from November 2, 2022 until May 1, 2023, are redeemable at 101.79% of par, and from May 2, 2023 to the maturity date are redeemable at 100% of par, in each case, in cash plus accrued interest.
Debt instrument covenant description			The financial covenants each as defined within the bond agreement are: (a) The issuer shall ensure that the Group (meaning “the Company and its subsidiaries”) maintains a minimum liquidity of no less than $25.0 million and (b) maintain a Group equity ratio of at least 30% (as defined in the 2018 Bond Agreement).
2018 Senior Secured Bonds [Member] | Minimum [Member]
Debt Instrument [Line Items]
Minimum liquidity to be maintained, amount				$ 25,000,000
Gross Equity ratio			30.00%
2018 Senior Secured Bonds [Member] | November 2, 2021 through November 1, 2022 [Member]
Debt Instrument [Line Items]
Debt instrument redeemable percentage	102.864%
2018 Senior Secured Bonds [Member] | November 2, 2022 through May 1, 2023 [Member]
Debt Instrument [Line Items]
Debt instrument redeemable percentage	101.79%
2018 Senior Secured Bonds [Member] | May 2, 2023 through Maturity Date [Member]
Debt Instrument [Line Items]
Debt instrument redeemable percentage	100.00%
2018 Senior Secured Bonds [Member] | Redemption of Bonds [Member]
Debt Instrument [Line Items]
Debt instrument redeemable percentage			101.00%
Senior Secured Bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Dividend payable percentage			50.00%
Nordea Bank Abp [Member] | 2018 Senior Secured Bonds [Member]
Debt Instrument [Line Items]
Aggregate principal amount					kr 600,000,000	$ 71,700,000
Debt instrument variable rate description	6.608% plus 3-month U.S. LIBOR

Senior Secured Bond - Schedule

Senior Secured Bond - Schedule of Breakdown of Senior Secured Bond and Total Deferred Financing Costs (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total	$ 815,942	$ 685,930
Senior Secured Bonds [Member]
Debt Instrument [Line Items]
Total Bond	68,154	70,299
Less deferred financing costs	(466)	(719)
Total	$ 67,688	$ 69,580

Senior Unsecured Bond - Additio

Senior Unsecured Bond - Additional Information (Detail) - USD ($) $ in Thousands	Nov. 02, 2018	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Sep. 30, 2020	Sep. 10, 2020
Debt Instrument [Line Items]
Interest rate on bond		7.75%		7.75%
Interest payment description on bond	Interest is payable quarterly in arrears on February 2, May 2, August 2 and November 2.
Debt instrument covenant description			financial covenants (each as defined within the bond agreement governing the 2020 Bonds (the “2020 Bond Agreement”)) are: (a) The issuer shall ensure that the Group (meaning “the Company and its subsidiaries”) maintains a minimum liquidity of no less than $35.0 million; and (b) maintain a Group equity ratio (as defined in the 2020 Bond Agreement) of at least 30%. As of December 31, 2021, the Company was in compliance with all covenants for the 2020 Bonds.	The 2020 Bond Agreement provides that we may declare or pay dividends to shareholders provided that the Company maintains a minimum liquidity of $60.0 million unless an event of default has occurred and is continuing. The 2020 Bond Agreement also limits us and our subsidiaries from, among other things, entering into mergers and divestitures, engaging in transactions with affiliates or incurring any additional liens which would have a material adverse effect. In addition, the 2020 Bond Agreement includes customary events of default, including those relating to a failure to pay principal or interest, a breach of covenant, false representation and warranty, a cross-default to other indebtedness, the occurrence of a material adverse effect, or our insolvency or dissolution.
Minimum liquidity to be maintained, amount		$ 123,886	$ 59,056	$ 123,886
2020 Senior Unsecured Bonds [Member]
Debt Instrument [Line Items]
Aggregate principal amount						$ 100,000
Interest rate on bond						8.00%
Debt instrument maturity date			Sep. 10, 2025
Interest payment description on bond			Interest is payable semi-annually in arrears on March 10 and September 10.
Debt instrument covenant description			The 2020 Bonds are redeemable by the Company, in whole or in part, at any time. Any 2020 Bonds redeemed; up until September 9, 2023 will be priced at the aggregate of the net present value (based on the Norwegian government bond rate plus 50 basis points) of 103.2% of par and interest payable up to September 9, 2023; from September 10, 2023 up until September 9, 2024, are redeemable at 103.2% of par; from September 10, 2024 up until March 9, 2025, are redeemable at 101.6% of par, and from March 10, 2025 to the maturity date are redeemable at 100% of par, in each case, in cash plus accrued interest.
Deferred issuance costs		$ 1,449	$ 1,842	1,449	$ 2,000
2020 Senior Unsecured Bonds [Member] | Norwegian Government Bond [Member]
Debt Instrument [Line Items]
Debt instrument redemption description		Norwegian government bond rate plus 50 basis points
2020 Senior Unsecured Bonds [Member] | Minimum [Member]
Debt Instrument [Line Items]
Minimum liquidity to be maintained, amount		$ 35,000		$ 35,000
2020 Senior Unsecured Bonds [Member] | Maximum [Member]
Debt Instrument [Line Items]
Gross Equity ratio			30.00%
2020 Senior Unsecured Bonds [Member] | Until September 9, 2023
Debt Instrument [Line Items]
Debt instrument redeemable percentage			103.20%
2020 Senior Unsecured Bonds [Member] | September 10 ,2023 Up Until September 9 ,2024
Debt Instrument [Line Items]
Debt instrument redeemable percentage			103.20%
2020 Senior Unsecured Bonds [Member] | September 10 ,2024 Up Until September 9 ,2025
Debt Instrument [Line Items]
Debt instrument redeemable percentage			101.60%

Senior Unsecured Bond - Schedul

Senior Unsecured Bond - Schedule of Breakdown of Senior Unsecured Bond and Total Deferred Financing Costs (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Sep. 30, 2020
Debt Instrument [Line Items]
Total	$ 815,942	$ 685,930
2020 Senior Unsecured Bonds [Member]
Debt Instrument [Line Items]
Total Bond	100,000	100,000
Less deferred financing costs	(1,449)	(1,842)	$ (2,000)
Total	$ 98,551	$ 98,158

Loss per Share - Calculation of

Loss per Share - Calculation of Basic and Diluted Number of Weighted Average Outstanding Shares (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Earnings Per Share [Abstract]
Basic and diluted loss available to common stockholders of Navigator Holdings Ltd (in thousands)	$ (30,964)	$ (443)	$ (16,706)
Basic weighted average number of shares	64,669,567	55,885,376	55,792,711
Effect of dilutive potential share options:	0	0	0
Diluted weighted average number of shares	64,669,567	55,885,376	55,792,711

Loss per Share - Calculation _2

Loss per Share - Calculation of Basic and Diluted Number of Weighted Average Outstanding Shares (Parenthetical) (Detail) - shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Earnings Per Share [Abstract]
Effect of dilutive potential shares	0	0	0
Potential dilutive shares excluded computation of earnings per share	331,761	344,472	349,870

Share-Based Compensation - Addi

Share-Based Compensation - Additional Information (Detail) - USD ($)	Oct. 31, 2021	Oct. 31, 2020	Apr. 30, 2020	Mar. 19, 2020	Aug. 14, 2019	Mar. 20, 2019	Mar. 17, 2015	Apr. 30, 2020	Mar. 19, 2020	Mar. 20, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares authorized for grant											3,000,000
Granted, Number of shares				35,920						29,295		27,125
Restricted stock unit, vesting in period											286,895	89,888
Weighted average grant value per share, vested											$ 10.66	$ 12.25
Share-based compensation costs											$ 1,373,292	$ 1,321,205	$ 1,495,412
Share-based compensation costs											$ 0	$ 77,364
Share based compensation options exercisable											310,856
weighted average exercise price of share options exercisable											$ 21.37
weighted-average remaining contractual term of options outstanding											2 years 7 months 28 days
Shares granted forfieted		10,054	2,144		5,425						16,123	12,198
Sharebased Compensation Arrangement By Sharebased Payment Award Discounted Percenatge											15.00%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)							4 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)							6 years 6 months
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation cost not yet recognized											$ 380,704	$ 1,002,608
Total compensation cost not yet recognized period for recognition											1 year 21 days	11 months 4 days
2013 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Number of shares														63,728
Weighted average value, per share												$ 11.06
Restricted stock unit, vesting in period												17,240	94,764
Weighted average grant value per share, vested											$ 7.90			$ 12.04
Share vested, total fair value													$ 12,040	$ 274,240
Total compensation cost not yet recognized											$ 0	$ 0
Share-based compensation costs													$ 8,474
2013 Long Term Incentive Plan [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Number of shares	15,000
Weighted average value, per share	$ 8.46
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sharebased Compensation Arrangement By Sharebased Payment Award Discounted Purchase Price											$ 9.70
Non Employee Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Number of shares											30,380
Non Employee Director [Member] | 2013 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Number of shares								5,000	37,975
Weighted average value, per share				$ 7.90		$ 11.06				$ 10.26			$ 7.90
Restricted stock unit, vesting in period						32,550							29,898
Weighted average grant value per share, vested													$ 12.04
Share vested, total fair value											$ 295,294	$ 114,739	$ 336,054
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Intrinsic Value, Amount Per Share		$ 11.54			$ 11.06
Non Employee Director [Member] | 2013 Long Term Incentive Plan [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average value, per share												$ 11.06
Chief Executive Officer [Member] | 2013 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Number of shares											48,147	62,763
Weighted average value, per share											$ 7.90	$ 12.77	$ 15.80
Share vested, total fair value													$ 60,300
Chief Executive Officer [Member] | 2013 Long Term Incentive Plan [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average value, per share											$ 11.06
Officers and Employees [Member] | 2013 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Number of shares						141,888			17,240	23,957	32,521			28,214
Weighted average grant value per share, vested											$ 9.89
Share vested, total fair value											$ 293,175	$ 265,487	$ 548,218
Officers and Employees [Member] | 2013 Long Term Incentive Plan [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Number of shares										20,048
Weighted average value, per share										$ 10.26
Executive Chairman [Member] | 2013 Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock unit, vesting in period											20,048
Weighted average grant value per share, vested											$ 10.26
Share vested, total fair value											$ 1,777,532

Share-Based Compensation - Rest

Share-Based Compensation - Restricted Share Grant Activity (Detail) - $ / shares	Oct. 31, 2020	Apr. 30, 2020	Aug. 14, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Number of RSUs
Unvested, beginning balance				306,242	329,156
Granted				100,263	79,172
Forfeited	(10,054)	(2,144)	(5,425)	(16,123)	(12,198)
Vested				(286,895)	(89,888)
Unvested, ending balance				103,487	306,242	329,156
Weighted-average grant date fair value
Unvested, beginning balance				$ 10.54	$ 11.68
Granted				9.99	7.90
Vested				10.66	12.25
Unvested, ending balance				9.92	10.54	$ 11.68
Forfeited				$ 8.89	$ 11.54
Weighted-average remaining contractual terms (Years)
Weighted-average remaining contractual terms (Years)				1 year 21 days	11 months 4 days	1 year 4 months 17 days

Share-Based Compensation - Summ

Share-Based Compensation - Summary of Stock Option Activity (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Options
Beginning Balance	339,936	349,936
Post vesting cancellations during the year	29,080	10,000
Ending Balance	310,856	339,936
Weighted-Average Exercise Price
Beginning Balance	$ 21.40	$ 21.39
Post vesting cancellations during the year	20.45	20.82
Ending Balance	$ 21.37	$ 21.40

Commitments and Contingencies -

Commitments and Contingencies - Summary of Contractual Obligations (Detail) - USD ($) $ in Thousands		Dec. 31, 2021	Dec. 31, 2020
Contractual Obligation Fiscal Year Maturity [Line Items]
2022		$ 151,586	$ 67,936
2023		229,460	124,479
2024		209,633	202,353
2025		92,381	175,413
2026		50,403	54,388
Total		815,942	$ 685,930
2022		152,061
2023		301,401
2024		210,632
2025		193,714
2026		106,303
Thereafter		29,005
Total		993,116
Navigator Aurora Facility [Member]
Contractual Obligation Fiscal Year Maturity [Line Items]
2026	[1]	54,767
Total	[1]	54,767
Office operating leases [Member]
Contractual Obligation Fiscal Year Maturity [Line Items]
2022	[2]	475
2023	[2]	244
2024	[2]	999
2025	[2]	1,334
2026	[2]	1,133
Thereafter	[2]	1,403
Total	[2]	5,588
Secured term loan facilities and revolving credit facilities [Member]
Contractual Obligation Fiscal Year Maturity [Line Items]
2022		151,586
2023		229,460
2024		209,633
2025		92,380
2026		50,403
Thereafter		27,602
Total		761,064
2018 Bonds [Member]
Contractual Obligation Fiscal Year Maturity [Line Items]
2023		71,697
Total		71,697
2020 Bonds [Member]
Contractual Obligation Fiscal Year Maturity [Line Items]
2025		100,000
Total		$ 100,000
[1]	The Navigator Aurora Facility is a loan facility held within a lessor entity (for which legal ownership resides with financial institutions) that we are required to consolidate under U.S. GAAP into our financial statements as a variable interest entity. Please read Note 10—Variable Interest Entities to our consolidated financial statements.
[2]	The Company occupies office space in London with a lease that will commence in January 2022 for a period of 10 years with a mutual break option in January 2025, which is the fifth anniversary from the lease commencement date.The Company entered into a lease for office space in New York that now expires on May 31, 2022. The annual gross rent under this lease is approximately $0.4 million, subject to certain adjustments. The lease term for our representative office in Gdynia, Poland was revised during 2021 for an amended period to May 31, 2025. The gross rent per year is approximately $64,000. The Company occupies office space in Denmark with a lease commenced in September 2021 that now expires in December 2025. The gross rent per year is approximately $180,000.The weighted average remaining contractual lease term for the above four office leases on December 31, 2021, was 3.1 years (December 31, 2020: 1.2 years).

Commitments and Contingencies_2

Commitments and Contingencies - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Schedule Of Commitments And Contingencies [Line Items]
Weighted Average Remaining Lease Tenure	3 years	5 years 7 months 6 days
Office Space [Member]
Schedule Of Commitments And Contingencies [Line Items]
Weighted Average Remaining Lease Tenure	3 years 1 month 6 days	1 year 2 months 12 days
POLAND [Member]
Schedule Of Commitments And Contingencies [Line Items]
Operating lease future minimum payment per year	$ 64,000
Lease expiration date	May 31, 2025
London [Member]
Schedule Of Commitments And Contingencies [Line Items]
Lease term	10 years
Lease term, mutual break clause	5 years
NEW YORK [Member]
Schedule Of Commitments And Contingencies [Line Items]
Operating lease future minimum payment per year	$ 400,000
Lease expiration date	May 31, 2022
DENMARK
Schedule Of Commitments And Contingencies [Line Items]
Operating lease future minimum payment per year	$ 180,000
Lease expiration date	Dec. 1, 2025

Operating Lease Liabilities - A

Operating Lease Liabilities - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Operating Lease Weighted Average Discount Rate	3.20%	5.56%
Remaing Lease Period	3 years	5 years 7 months 6 days
Operating lease liabilities	$ 903	$ 6,508
Operating lease right of use asset	923	5,701
Operating Lease, Cost	$ 700	$ 1,400

Operating Lease Liabilities - M

Operating Lease Liabilities - Maturity Analysis of The Undiscounted Cash Flows of The Company's Operating Lease Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Operating Lease Liabilities [Abstract]
One year	$ 398	$ 1,572
Two years	181	1,300
Three years	181	1,144
Four years	181	1,144
Five years	0	1,144
Six years and thereafter	0	1,222
Total undiscounted operating lease commitments	941	7,526
Less: Discount adjustment	(38)	(1,018)
Total operating lease liabilities	903	6,508
Less: current portion	(381)	(1,276)
Operating lease liabilities, non-current portion	$ 522	$ 5,232

Concentration of Credit Risks -

Concentration of Credit Risks - Additional Information (Detail) - Sales Revenue, Net [Member] $ in Millions	12 Months Ended
	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)
Product Concentration Risk [Member]
Concentration Risk [Line Items]
Number of charterers	2	2
Product Concentration Risk [Member] | Minimum [Member]
Concentration Risk [Line Items]
Percentage of operating revenue		10.00%
Product Concentration Risk [Member] | One Time Charter [Member]
Concentration Risk [Line Items]
Percentage of operating revenue	10.00%	12.80%
Concentration risk, amount		$ 41
Product Concentration Risk [Member] | Two Time Charter [Member]
Concentration Risk [Line Items]
Percentage of operating revenue		12.30%
Concentration risk, amount		$ 39.6
Product Concentration Risk [Member] | One and Two Time Charter [Member]
Concentration Risk [Line Items]
Concentration risk, amount	$ 73.2
Concentration Risk Percentage Aggregate	20.70%
Revenue from Rights Concentration Risk [Member] | Indonesia
Concentration Risk [Line Items]
Percentage of operating revenue	5.60%	9.30%

Income Taxes - Summary of Incom

Income Taxes - Summary of Income Tax Reconciliation (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Contingency [Line Items]
(Loss)/income before income taxes and share of result of equity method investments	$ (38,394)	$ 1,279	$ (15,129)
Tax expense at statutory rate	0	0	0
Total statutory tax charge	0	0	0
Breakdown of current/deferred tax expense
Current tax expense	1,264	489	524
Deferred tax expense	705	128	(172)
Total Tax charge	1,969	617	352
UNITED STATES
Breakdown of current/deferred tax expense
Total Tax charge	855	0	0
UNITED KINGDOM [Member]
Breakdown of current/deferred tax expense
Total Tax charge	566	416	199
POLAND [Member]
Breakdown of current/deferred tax expense
Total Tax charge	345	31	(65)
SINGAPORE [Member]
Breakdown of current/deferred tax expense
Total Tax charge	47	77	213
DENMARK
Breakdown of current/deferred tax expense
Total Tax charge	74	0	0
MALTA [Member]
Breakdown of current/deferred tax expense
Total Tax charge	$ 82	$ 93	$ 5

Income Tax - Summary of Deferre

Income Tax - Summary of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax asset
Net operating losses carry forwards	$ 21,592	$ 19,601
Other temporary differences	388	0
Total deferred tax assets	21,980	19,601
Less valuation allowance	0	(1,731)
Deferred tax asset, net of valuation allowance	21,980	17,870
Deferred tax liabilities
Investment in joint venture	21,871	17,449
Other temporary differences	517	32
Total deferred tax liabilities	22,388	17,481
Net deferred tax asset/(liability)	$ 408	$ 389

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Defered Tax Assets	$ 463,000	$ 421,000
Defered Tax Liabilities	871,000	$ 32,000
Income Tax, Carry Forwards	400,000
Defered Tax Assets	80,000
Losses Carry Forward	400,000
Export Terminal Joint Venture [Member]
Defered Tax Assets	22,000,000
Income Tax, Carry Forwards	$ 21,500,000
Percentage of carry forwards utilized against future profits	80.00%

Cash,Cash Equivalents and Restr

Cash,Cash Equivalents and Restricted Cash - Schedule of breakdown of cash, cash equivalents and restricted cash (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Cash, Cash Equivalents and Restricted Cash
Cash and cash equivalents	$ 123,886	$ 59,056
Cash and cash equivalents held by the lessor VIE (note 10)	124,223	59,271
Total cash, cash equivalents and restricted cash	124,223	59,271
Variable Interest Entity, Primary Beneficiary [Member]
Cash, Cash Equivalents and Restricted Cash
Cash and cash equivalents	300
Cash and cash equivalents held by the lessor VIE (note 10)	337	215
Total cash, cash equivalents and restricted cash	$ 337	$ 215

Cash,Cash Equivalents and Res_2

Cash,Cash Equivalents and Restricted Cash - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Cash, cash equivalents and restricted cash	$ 124,223	$ 59,271
Cash and cash equivalent carrying value	$ 123,886	59,056
Liquidity as percentage of net debt.	5.00%
Criteria One [Member]
Liquidity to be maintained as part of debt covenant	$ 25,000
Criteria Two [Member]
Liquidity to be maintained as part of debt covenant	35,000
Criteria Three [Member]
Liquidity to be maintained as part of debt covenant	50,000
Criteria Four [Member]
Liquidity to be maintained as part of debt covenant	49,200
Variable Interest Entity, Primary Beneficiary [Member]
Cash, cash equivalents and restricted cash	337	$ 215
Cash and cash equivalent carrying value	$ 300

Related Party Transactions - Sc

Related Party Transactions - Schedule of Related Party Transactions Income Expenses (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Schedule of Related Party Transactions Income Expenses [Line Items]
Net income / (expenses)	$ (2,193)	$ (1,827)
Luna Pool Agency Limited [Member]
Schedule of Related Party Transactions Income Expenses [Line Items]
Net income / (expenses)	(30)
Ocean Yield Malta Limited [Member]
Schedule of Related Party Transactions Income Expenses [Line Items]
Net income / (expenses)	(1,202)	$ (1,827)
Ultranav Business Support ApS [Member]
Schedule of Related Party Transactions Income Expenses [Line Items]
Net income / (expenses)	(936)
Naviera Ultranav Limitada [Member]
Schedule of Related Party Transactions Income Expenses [Line Items]
Net income / (expenses)	$ (25)

Related Party Transactions - _2

Related Party Transactions - Schedule of Related Party Transaction Due From Related Party (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Due from Related Parties, Current	$ 16,736	$ 11,853
Luna Pool Agency Limited [Member]
Related Party Transaction [Line Items]
Due from Related Parties, Current	8,450	$ 11,853
Unigas Pool [Member]
Related Party Transaction [Line Items]
Due from Related Parties, Current	8,049
Dan Unity [Member]
Related Party Transaction [Line Items]
Due from Related Parties, Current	109
Naviera Ultranav Limitada [Member]
Related Party Transaction [Line Items]
Due from Related Parties, Current	$ 128

Related Party Transactions - _3

Related Party Transactions - Schedule of Related Party Transaction Due To Related Party (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Due to Related Parties, Current	$ 55,101	$ 61,448
Ocean Yield Malta Limited [Member]
Related Party Transaction [Line Items]
Due to Related Parties, Current	55,074	$ 61,448
Naviera Ultranav Limitada [Member]
Related Party Transaction [Line Items]
Due to Related Parties, Current	$ 27

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Aug. 04, 2021	Dec. 31, 2020
Business Acquisition, Common Stock Issued	77,180,429		55,893,618
Naviera Ultranav Limitada [Member]
Holding percentage of share	27.50%
Naviera Ultranav Limitada [Member]
Business Acquisition, Percentage of Voting Interests Acquired		27.50%
Common Stock [Member] | Naviera Ultranav Limitada [Member]
Business Acquisition, Common Stock Issued		21,202,671
Ultranav Business Support ApS [Member]
Related Party, Service Cost		$ 173,659

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Common stock, authorized	400,000,000	400,000,000
Preferred Stock, authorized	40,000,000
Common stock, par value	$ 0.01	$ 0.01
Preferred stock, par value	$ 0.01
Common stock, shares issued	77,180,429	55,893,618
Common stock, shares outstanding	77,180,429	55,893,618
Preferred stock, shares issued	0
Preferred stock, shares outstanding	0
Common stock voting rights	one

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) $ in Millions	Mar. 07, 2022USD ($)m³	Jan. 14, 2022USD ($)m³	Dec. 31, 2021OfficersVessels
Russian and Ukrainian Officers [Member] | Global Fleet [Member]
Subsequent Event [Line Items]
Number of employee | Vessels			120
Russian Officers [Member] | Global Fleet [Member]
Subsequent Event [Line Items]
Number of employee | Officers			70,000
Ukrainian Officers [Member] | Global Fleet [Member]
Subsequent Event [Line Items]
Number of employee | Officers			50,000
Ethylene Carrier [Member]
Subsequent Event [Line Items]
Contract with Customer, Asset, Sale		$ 21
Vessels Cargo Capacity | m³		22,085
LPG Carrier [Member]
Subsequent Event [Line Items]
Contract with Customer, Asset, Sale	$ 6.1
Vessels Cargo Capacity | m³	8,600
2018 Bond [Member]
Subsequent Event [Line Items]
Debt instrument maturity date		Nov. 30, 2023
Debt Instrument, Convertible, Beneficial Conversion Feature		$ 20.6
Debt Instrument, Convertible, Conversion Ratio		1.02