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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 42
-URI http://asc.fasb.org/extlink&oid=68060357&loc=d3e9054-108599

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Segment Information - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2017	Mar. 31, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Revenues	$ 225,735		$ 216,975	$ 697,796	$ 662,971
Operating income	$ 11,423		$ (9,353)	(23,397)	100,787
BHMI judgment and related fees and interest expense		$ 2,700		48,100
General and Administrative Expense [Member]
Segment Reporting Information [Line Items]
BHMI judgment and related fees and interest expense				$ 46,700
Geographic Concentration Risk
Segment Reporting Information [Line Items]
Percentage of revenues during the three and nine months ended September 30, 2017 and 2016	No other country outside the United States accounted for more than 10% of the Company's consolidated revenues during the three and nine months ended September 30, 2017 and 2016.			No other country outside the United States accounted for more than 10% of the Company's consolidated revenues during the three and nine months ended September 30, 2017 and 2016.
Customer Concentration Risk [Member]
Segment Reporting Information [Line Items]
Percentage of revenues during the three and nine months ended September 30, 2017 and 2016	No single customer accounted for more than 10% of the Company's consolidated revenues during the three and nine months ended September 30, 2017 and 2016.			No single customer accounted for more than 10% of the Company's consolidated revenues during the three and nine months ended September 30, 2017 and 2016.
Corporate and Other [Member] \| Community Financial Services Products [Member]
Segment Reporting Information [Line Items]
Revenues					15,400
Operating income					$ 151,700