Nature of Operations and Basis of Presentation - Previously Reported Consolidated Statement of Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Nature of Operations and Basis of Presentation [Line Items]
Deferred taxes and other adjustments, net					$ 7,473	$ 5,223
Net Cash Provided by (Used in) Operating Activities					70,284	57,787
Effect of exchange rate changes on cash					640	(596)
Increase in Cash, Cash Equivalents, and Restricted Cash					(149)	1,865
Cash and Cash Equivalents, Beginning Period	$ 6,042	$ 7,747	$ 6,042	$ 7,747	6,042	7,747
Cash, Cash Equivalents, and Restricted Cash, Beginning of Period	7,885	9,109	7,885	9,109	7,885	9,109
Cash and Cash Equivalents, End of Period					6,485	9,647
Cash, Cash Equivalents, and Restricted Cash, End of Period					7,736	10,974
New Accounting Pronouncement Early Adoption Effect \| ASU 2016-18
Nature of Operations and Basis of Presentation [Line Items]
Deferred taxes and other adjustments, net						5,223
Net Cash Provided by (Used in) Operating Activities	6,102	(13,365)	16,645	15,740		57,787
Effect of exchange rate changes on cash	34	449	367	405		(596)
Increase in Cash, Cash Equivalents, and Restricted Cash	1,569	1,624	2,862	3,104		1,865
Cash, Cash Equivalents, and Restricted Cash, Beginning of Period	7,885	9,109	7,885	9,109	7,885	9,109
Cash, Cash Equivalents, and Restricted Cash, End of Period	9,454	10,733	10,747	12,213		10,974
New Accounting Pronouncement Early Adoption Effect \| ASU 2016-18 \| As Reported
Nature of Operations and Basis of Presentation [Line Items]
Restricted cash	603	(12)	597	(3)
Deferred taxes and other adjustments, net						5,254
Net Cash Provided by (Used in) Operating Activities	6,705	(13,377)	17,242	15,737		57,818
Effect of exchange rate changes on cash	41	449	359	405		(592)
Increase (Decrease) in Cash and Cash Equivalents	2,165	1,612	3,451	3,101		1,900
Cash and Cash Equivalents, Beginning Period	6,042	7,747	6,042	7,747	$ 6,042	7,747
Cash and Cash Equivalents, End of Period	$ 8,207	$ 9,359	$ 9,493	$ 10,848		$ 9,647

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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