Stock Based Compensation - Non-vested Restricted Stock, PSU and RSU Award Activity (Details) - $ / shares	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Restricted Stock
Number of Non-vested Restricted Shares
Non-vested shares at beginning of period (in shares)	1,909,107	1,603,766
Granted (in shares)	1,217,671	939,446
Vested (in shares)	(884,959)	(621,438)
Forfeited (in shares)	(59,834)	(19,430)
Non-vested shares at end of period (in shares)	2,181,985	1,902,344
Weighted Average Per Share Grant Date Fair Value
Non-vested shares at beginning of period (in dollars per share)	$ 5.05	$ 6.27
Granted (in dollars per share)	3.59	3.82
Vested (in dollars per share)	5.49	5.41
Forfeited (in dollars per share)	3.96	3.26
Non-vested shares at end of period (in dollars per share)	$ 4.08	$ 5.09
PSUs, Target
Number of Non-vested Restricted Shares
Non-vested shares at beginning of period (in shares)	3,376,740	2,902,014
Granted (in shares)	844,534	1,631,661
Vested (in shares)	(1,074,918)	(842,792)
Non-vested shares at end of period (in shares)	3,146,356	3,690,883
PSUs
Number of Non-vested Restricted Shares
Vested (in shares)	(733,496)	(974,074)
Weighted Average Per Share Grant Date Fair Value
Non-vested shares at beginning of period (in dollars per share)	$ 5.43	$ 4.98
Granted (in dollars per share)	4.87	5.56
Vested (in dollars per share)	4.00	4.20
Non-vested shares at end of period (in dollars per share)	$ 5.76	$ 5.41
RSUs
Number of Non-vested Restricted Shares
Non-vested shares at beginning of period (in shares)	1,016,252	441,746
Granted (in shares)	422,267	815,830
Vested (in shares)	(383,639)	(147,254)
Non-vested shares at end of period (in shares)	1,054,880	1,110,322
Weighted Average Per Share Grant Date Fair Value
Non-vested shares at beginning of period (in dollars per share)	$ 4.36	$ 6.23
Granted (in dollars per share)	3.72	3.69
Vested (in dollars per share)	4.58	6.23
Non-vested shares at end of period (in dollars per share)	$ 4.03	$ 4.36

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (c)(2)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Weighted average grant-date fair value of non-vested options forfeited.

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