Fair Value of Financial Assets and Liabilities (Tables)

6 Months Ended

Jun. 30, 2016

Fair Value Disclosures [Abstract]

Schedule of fair value of long-term debt, including current maturities and advances for construction

Advances for construction fair values were estimated using broker quotes from companies that frequently purchase these investments.

	June 30, 2016
			Fair Value
	Cost		Level 1		Level 2		Level 3		Total
Long-term debt, including current maturities	$	561,920	—		$	685,413	—		$	685,413
Advances for construction	180,429		—		74,483		—		74,483
Total	$	742,349	$	—	$	759,896	$	—	$	759,896

	December 31, 2015
			Fair Value
	Cost		Level 1		Level 2		Level 3		Total
Long-term debt, including current maturities	$	514,045	$	—	$	600,440	$	—	$	600,440
Advances for construction	180,172		—		72,866		—		72,866
Total	$	694,217	—		$	673,306	$	—	$	673,306