Equity and EPS - Dividends (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended	12 Months Ended
Sep. 11, 2017	Sep. 08, 2017	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Equity [Abstract]
Dividends declared (in dollars per share)	$ 0.04	$ 0.85	$ 0.10	$ 0.10	$ 0.10	$ 0.10	$ 0.08	$ 0.08	$ 0.08	$ 0.08	$ 0.04	$ 0.04	$ 0.04	$ 0.40	$ 0.32	$ 1.01
Dividends paid (in dollars per share)	$ 0.04	$ 0.85	$ 0.10	$ 0.10	$ 0.10	$ 0.10	$ 0.08	$ 0.08	$ 0.08	$ 0.08	$ 0.04	$ 0.04	$ 0.04	$ 0.40	$ 0.32	$ 1.01
Dividend payment	$ 669	$ 14,215	$ 1,703	$ 1,703	$ 1,702	$ 1,701	$ 1,349	$ 1,348	$ 1,348	$ 1,348	$ 669	$ 668	$ 668	$ 6,809	$ 5,393	$ 16,889
Dividend equivalent payment	19	413	12	11	11	13	26	27	27	27	19	20	20	47	107	491
Total payment	$ 688	$ 14,628	$ 1,715	$ 1,714	$ 1,713	$ 1,714	$ 1,375	$ 1,375	$ 1,375	$ 1,375	$ 688	$ 688	$ 688	$ 6,856	$ 5,500	$ 17,380

Aggregate dividends paid during the period for each share of common stock outstanding.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in stock.

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