Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Intangible Assets (Excluding Goodwill) [Line Items]
Definite-lived intangible assets, gross carrying amount	$ 128,088	$ 170,006
Definite-lived intangible assets, accumulated amortization	77,104	109,647
Total	50,984	60,359
Total intangible assets, gross carrying amount	163,538	205,998
Total intangible assets, accumulated amortization	85,357	117,900
Total intangible assets, net carrying amount	78,181	88,098	$ 98,645
Non-compete agreements [Member]
Intangible Assets (Excluding Goodwill) [Line Items]
Definite-lived intangible assets, gross carrying amount	2,254	11,901
Definite-lived intangible assets, accumulated amortization	2,170	11,548
Total	84	353
Customer relationships
Intangible Assets (Excluding Goodwill) [Line Items]
Definite-lived intangible assets, gross carrying amount	122,345	137,267
Definite-lived intangible assets, accumulated amortization	71,445	77,988
Total	50,900	59,279
Total intangible assets, net carrying amount	50,900	59,279	68,623
Backlog
Intangible Assets (Excluding Goodwill) [Line Items]
Definite-lived intangible assets, gross carrying amount	3,489	20,838
Definite-lived intangible assets, accumulated amortization	3,489	20,111
Total	0	727
Total intangible assets, net carrying amount	0	727	1,599
Trademarks
Intangible Assets (Excluding Goodwill) [Line Items]
Indefinite-lived intangible assets, gross carrying amount	35,450	35,992
Indefinite-lived intangible assets, accumulated amortization	8,253	8,253
Indefinite-lived intangible assets, net carrying amount	27,197	27,739
Total intangible assets, net carrying amount	$ 27,197	$ 27,739	$ 27,739