Condensed Consolidated Statements of Cash Flows - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities:
Net income	$ 53,073,000	$ 9,849,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	11,697,000	10,507,000
Amortization of operating lease right-of-use assets	5,706,000	3,080,000
Amortization of deferred drydocking costs	2,883,000	1,999,000
Amortization of debt discount and debt issuance costs	562,000	1,629,000
Net unrealized loss/(gain) on fair value of derivatives	11,450,000	(503,000)
Stock-based compensation expense	1,487,000	872,000
Drydocking expenditures	(10,774,000)	(4,821,000)
Changes in operating assets and liabilities:
Accounts payable	3,010,000	6,488,000
Accounts receivable	(12,462,000)	(6,697,000)
Accrued interest	(1,445,000)	2,150,000
Inventories	(10,120,000)	(3,096,000)
Operating lease liabilities current and noncurrent	(5,706,000)	(3,302,000)
Collateral on derivatives	(6,226,000)	0
Fair value of derivatives, other current and noncurrent assets	(252,000)	(5,743,000)
Other accrued liabilities	628,000	159,000
Prepaid expenses	(1,916,000)	(308,000)
Unearned charter hire revenue	659,000	2,070,000
Net cash provided by operating activities	42,254,000	14,333,000
Cash flows from investing activities:
Purchase of vessels and vessel improvements	(283,000)	(47,977,000)
Advances for vessel purchases	0	(4,720,000)
Purchase of scrubbers and ballast water systems	(3,494,000)	(755,000)
Proceeds from hull and machinery insurance claims	0	75,000
Purchase of other fixed assets	(160,000)	(8,000)
Net cash used in investing activities	(3,937,000)	(53,385,000)
Cash flows from financing activities:
Cash received from exercise of stock options	85,000	0
Cash used to settle net share equity awards	(1,862,000)	(811,000)
Equity offerings issuance costs	201,000	(292,000)
Financing costs paid to lenders	(18,000)	(170,000)
Dividends paid	(26,818,000)	0
Net cash (used in)/provided by financing activities	(40,862,000)	30,916,000
Net decrease in cash, cash equivalents and restricted cash	(2,545,000)	(8,136,000)
Cash, cash equivalents and restricted cash at beginning of period	86,222,000	88,849,000
Cash, cash equivalents and restricted cash at end of period	83,677,000	80,713,000
SUPPLEMENTAL CASH FLOW INFORMATION
Cash paid during the period for interest	4,791,000	4,320,000
Accruals for vessel purchases and vessel improvements included in Other accrued liabilities	70,000	244,000
Accruals for scrubbers and ballast water treatment systems included in Accounts payable and Other accrued liabilities	2,943,000	3,153,000
Accruals for dividends payable included in Other accrued liabilities and Other noncurrent accrued liabilities	785,000	0
Accruals for debt issuance costs included in Accounts payable and Other accrued liabilities	0	250,000
New Ultraco Debt Facility | Term Loan
Cash flows from financing activities:
Repayments of long-term debt	0	(7,811,000)
New Ultraco Debt Facility | Revolver Loan
Cash flows from financing activities:
Proceeds from debt	0	55,000,000
Super Senior Facility | Revolver Loan
Cash flows from financing activities:
Repayments of long-term debt	0	(15,000,000)
Global Ultraco Debt Facility | Revolver Loan
Cash flows from financing activities:
Repayments of long-term debt	$ (12,450,000)	$ 0