Unaudited Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Cumulative effect of adoption of new accounting standards	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Deficit	Retained Deficit Cumulative effect of adoption of new accounting standards	Accumulated Other Comprehensive (Loss) Income	Non-controlling Interest
Common stock issued at the beginning of the period (shares) at Sep. 30, 2019			116,008,000
Stockholders' equity, balance at the beginning of the period at Sep. 30, 2019	$ 365,822	$ (2,023)	$ 1,154	$ (2,837)	$ 552,422	$ (174,976)	$ (2,023)	$ (13,004)	$ 3,063
Treasury stock, balance at the beginning of the period (in shares) at Sep. 30, 2019				1,664,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity based compensation expense	3,680				3,680
Issuance of common stock (in shares)			1,645,000	419,000
Issuance of common stock, net	4,046		$ 16		4,030
Dividends paid to non-controlling interest	(1,250)								(1,250)
Divestiture of Memcor product line	(16,895)
Net income	53,506					53,145			361
Other comprehensive income (loss)	8,244							8,244
Common stock issued at the end of the period (shares) at Dec. 31, 2019			117,653,000
Stockholders' equity, balance at the end of the period at Dec. 31, 2019	415,130	686	$ 1,170	$ (2,837)	543,237	(123,854)	686	(4,760)	2,174
Treasury stock, balance at the end of the period (in shares) at Dec. 31, 2019				2,083,000
Common stock issued at the beginning of the period (shares) at Sep. 30, 2019			116,008,000
Stockholders' equity, balance at the beginning of the period at Sep. 30, 2019	365,822	(2,023)	$ 1,154	$ (2,837)	552,422	(174,976)	(2,023)	(13,004)	3,063
Treasury stock, balance at the beginning of the period (in shares) at Sep. 30, 2019				1,664,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	83,257
Other comprehensive income (loss)	(8,120)
Common stock issued at the end of the period (shares) at Jun. 30, 2020			119,392,000
Stockholders' equity, balance at the end of the period at Jun. 30, 2020	447,330		$ 1,187	$ (2,837)	561,947	(93,972)		(21,124)	2,129
Treasury stock, balance at the end of the period (in shares) at Jun. 30, 2020				2,195,000
Common stock issued at the beginning of the period (shares) at Dec. 31, 2019			117,653,000
Stockholders' equity, balance at the beginning of the period at Dec. 31, 2019	415,130	$ 686	$ 1,170	$ (2,837)	543,237	(123,854)	$ 686	(4,760)	2,174
Treasury stock, balance at the beginning of the period (in shares) at Dec. 31, 2019				2,083,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity based compensation expense	2,304				2,304
Issuance of common stock (in shares)			1,417,000	111,000
Issuance of common stock, net	11,324		$ 15		11,309
Dividends paid to non-controlling interest	(200)								(200)
Net income	7,910					7,812			98
Other comprehensive income (loss)	(14,651)							(14,651)
Common stock issued at the end of the period (shares) at Mar. 31, 2020			119,070,000
Stockholders' equity, balance at the end of the period at Mar. 31, 2020	422,503		$ 1,185	$ (2,837)	556,850	(115,356)		(19,411)	2,072
Treasury stock, balance at the end of the period (in shares) at Mar. 31, 2020				2,194,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity based compensation expense	2,520				2,520
Issuance of common stock (in shares)			322,000	1,000
Issuance of common stock, net	2,579		$ 2		2,577
Dividends paid to non-controlling interest	(400)								(400)
Net income	21,841					21,384			457
Other comprehensive income (loss)	(1,713)							(1,713)
Common stock issued at the end of the period (shares) at Jun. 30, 2020			119,392,000
Stockholders' equity, balance at the end of the period at Jun. 30, 2020	$ 447,330		$ 1,187	$ (2,837)	561,947	(93,972)		(21,124)	2,129
Treasury stock, balance at the end of the period (in shares) at Jun. 30, 2020				2,195,000
Common stock issued at the beginning of the period (shares) at Sep. 30, 2020	119,486,000		119,486,000
Stockholders' equity, balance at the beginning of the period at Sep. 30, 2020	$ 482,063		$ 1,189	$ (2,837)	564,928	(62,664)		(20,472)	1,919
Treasury stock, balance at the beginning of the period (in shares) at Sep. 30, 2020	2,195,000			2,195,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity based compensation expense	$ 3,019				3,019
Issuance of common stock (in shares)			1,264,000	1,000
Issuance of common stock, net	14,263		$ 13		14,250
Dividends paid to non-controlling interest	(250)								(250)
Net income	6,477					6,433			44
Other comprehensive income (loss)	(3,611)							(3,611)
Common stock issued at the end of the period (shares) at Dec. 31, 2020			120,750,000
Stockholders' equity, balance at the end of the period at Dec. 31, 2020	$ 501,961		$ 1,202	$ (2,837)	582,197	(56,231)		(24,083)	1,713
Treasury stock, balance at the end of the period (in shares) at Dec. 31, 2020				2,196,000
Common stock issued at the beginning of the period (shares) at Sep. 30, 2020	119,486,000		119,486,000
Stockholders' equity, balance at the beginning of the period at Sep. 30, 2020	$ 482,063		$ 1,189	$ (2,837)	564,928	(62,664)		(20,472)	1,919
Treasury stock, balance at the beginning of the period (in shares) at Sep. 30, 2020	2,195,000			2,195,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 24,758								134
Other comprehensive income (loss)	$ 29,814
Common stock issued at the end of the period (shares) at Jun. 30, 2021	121,837,000		121,837,000
Stockholders' equity, balance at the end of the period at Jun. 30, 2021	$ 545,179		$ 1,219	$ (2,837)	573,892	(38,040)		9,342	1,603
Treasury stock, balance at the end of the period (in shares) at Jun. 30, 2021	1,664,000			1,664,000
Common stock issued at the beginning of the period (shares) at Dec. 31, 2020			120,750,000
Stockholders' equity, balance at the beginning of the period at Dec. 31, 2020	$ 501,961		$ 1,202	$ (2,837)	582,197	(56,231)		(24,083)	1,713
Treasury stock, balance at the beginning of the period (in shares) at Dec. 31, 2020				2,196,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity based compensation expense	3,214				3,214
Issuance of common stock (in shares)			692,000	(532,000)
Issuance of common stock, net	(21,364)		$ 13		(21,377)
Dividends paid to non-controlling interest	(100)								(100)
Net income	5,082					5,036			46
Other comprehensive income (loss)	36,092							36,092
Common stock issued at the end of the period (shares) at Mar. 31, 2021			121,442,000
Stockholders' equity, balance at the end of the period at Mar. 31, 2021	524,885		$ 1,215	$ (2,837)	564,034	(51,195)		12,009	1,659
Treasury stock, balance at the end of the period (in shares) at Mar. 31, 2021				1,664,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity based compensation expense	4,228				4,228
Issuance of common stock (in shares)			395,000	0
Issuance of common stock, net	5,634		$ 4		5,630
Dividends paid to non-controlling interest	(100)								(100)
Net income	13,199					13,155			44
Other comprehensive income (loss)	$ (2,667)							(2,667)
Common stock issued at the end of the period (shares) at Jun. 30, 2021	121,837,000		121,837,000
Stockholders' equity, balance at the end of the period at Jun. 30, 2021	$ 545,179		$ 1,219	$ (2,837)	$ 573,892	$ (38,040)		$ 9,342	$ 1,603
Treasury stock, balance at the end of the period (in shares) at Jun. 30, 2021	1,664,000			1,664,000