Long-Term Debt - Outstanding Long-Term Debt (Detail) - USD ($) $ in Thousands		Jun. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Total long-term debt		$ 151,800	$ 153,700
Capital lease obligation		4,153	4,824
Total Long-term debt		156,252	158,490
Less: current maturities		(12,075)	(9,151)
Less: debt issuance costs		(312)	(333)
Total long-term debt, net of current maturities		143,865	149,006
9.08% bond, due June 1, 2022 [Member]
Debt Instrument [Line Items]
Total long-term debt	[1]	7,976	7,973
6.64% note, due October 31, 2017 [Member]
Debt Instrument [Line Items]
Total long-term debt		5,455	5,455
5.50% note, due October 12, 2020 [Member]
Debt Instrument [Line Items]
Total long-term debt		10,000	10,000
5.93% note, due October 31, 2023 [Member]
Debt Instrument [Line Items]
Total long-term debt		22,500	24,000
5.68% note, due June 30, 2026 [Member]
Debt Instrument [Line Items]
Total long-term debt		29,000	29,000
Uncollateralized Senior Notes Due On May Two Thousand Twenty Eight [Member]
Debt Instrument [Line Items]
Total long-term debt		7,000	7,000
Uncollateralized Senior Note Two Due on December Two Thousand Twenty Eight [Member]
Debt Instrument [Line Items]
Total long-term debt		20,000	20,000
Uncollateralized Senior Notes Due On Two Thousand Twenty Nine [Member]
Debt Instrument [Line Items]
Total long-term debt		50,000	50,000
Promissory note [Member]
Debt Instrument [Line Items]
Total long-term debt		$ 168	$ 238

[1] FPU secured first mortgage bonds are guaranteed by Chesapeake Utilities.