Acquisitions (Details 3) (USD $)			9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended	3 Months Ended	9 Months Ended			9 Months Ended			9 Months Ended				9 Months Ended			9 Months Ended			9 Months Ended			9 Months Ended
	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2013 Vehicles Minimum	Mar. 31, 2013 Vehicles Minimum	Dec. 31, 2013 Vehicles Maximum	Mar. 31, 2013 Vehicles Maximum	Dec. 31, 2013 Water treatment facilities and equipment Minimum	Mar. 31, 2013 Water treatment facilities and equipment Minimum	Dec. 31, 2013 Water treatment facilities and equipment Maximum	Mar. 31, 2013 Water treatment facilities and equipment Maximum	Dec. 31, 2013 Buildings and leasehold improvements Minimum	Mar. 31, 2013 Buildings and leasehold improvements Minimum	Dec. 31, 2013 Buildings and leasehold improvements Maximum	Mar. 31, 2013 Buildings and leasehold improvements Maximum	Sep. 30, 2013 Other Water Services item	Dec. 31, 2013 Other Water Services	Dec. 31, 2013 Other Water Services Customer relationships	Dec. 31, 2013 Other Water Services Trade names	Dec. 31, 2013 Other Water Services Non-compete agreements	Dec. 31, 2013 Other Water Services Water facility development agreement	Dec. 31, 2013 Other Water Services Water facility option agreement	Dec. 31, 2013 Other Water Services Minimum Customer relationships	Dec. 31, 2013 Other Water Services Maximum Customer relationships	Dec. 31, 2013 Other Water Services Land	Dec. 31, 2013 Other Water Services Vehicles	Dec. 31, 2013 Other Water Services Vehicles Minimum	Dec. 31, 2013 Other Water Services Vehicles Maximum	Dec. 31, 2013 Other Water Services Water treatment facilities and equipment	Dec. 31, 2013 Other Water Services Water treatment facilities and equipment Minimum	Dec. 31, 2013 Other Water Services Water treatment facilities and equipment Maximum	Dec. 31, 2013 Other Water Services Buildings and leasehold improvements	Dec. 31, 2013 Other Water Services Buildings and leasehold improvements Minimum	Dec. 31, 2013 Other Water Services Buildings and leasehold improvements Maximum	Dec. 31, 2013 Other Water Services Other	Dec. 31, 2013 Other Water Services Other Minimum	Dec. 31, 2013 Other Water Services Other Maximum
Acquisitions
Number of business acquired															2
Number of common units issued to acquire business (in shares)															222,381
General and administrative expense																$ 300,000
Revenues																11,300,000
Operating income																3,600,000
Estimated fair value of the assets acquired and liabilities assumed
Accounts receivable - trade																1,959,000
Inventories																192,000
Other current assets																112,000
Property, plant and equipment																								206,000	90,000			15,683,000			616,000			12,000
Useful life of property, plant and equipment			5 years	5 years	10 years	10 years	3 years	3 years	30 years	30 years	5 years	5 years	30 years	30 years												5 years	10 years		3 years	30 years		7 years	30 years		3 years	5 years
Intangible assets																	56,750,000	2,800,000	260,000	14,000,000	2,500,000
Useful life of intangible assets																			3 years	5 years		5 years	10 years
Goodwill	1,037,237,000	563,146,000														63,370,000
Trade accounts payable																(82,000)
Accrued expenses																(273,000)
Other noncurrent liabilities																(64,000)
Fair value of net assets acquired																158,131,000
Consideration paid for acquisition
Cash paid, net of cash acquired																151,337,000
Value of common units issued																6,794,000
Total consideration paid																$ 158,131,000