Interest Rate Swap Agreements - Summary of locations and amounts of losses in income (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Periodic change in fair value of interest rate swap agreements	$ 222	$ (24)	$ (364)
Periodic settlement differentials included in interest expense	(179)	(343)
Gain (loss) recognized in income	$ 43	$ (367)

Amount of unrealized gain (loss) related to the fair value of interest rate derivatives designated as fair value hedging instruments, as offset by the gain (loss) on the hedged item to the extent that the fair value hedge is determined to be effective.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration