Goodwill and Other Intangible Assets (Details Textuals)	3 Months Ended		6 Months Ended	12 Months Ended
	Mar. 31, 2017 USD ($) acquisition	Mar. 31, 2016 USD ($) acquisition	Jun. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)
Business Acquisition [Line Items]
Goodwill acquired during period	$ 55,000	$ 3,000,000
Additions to finite-lived intangible assets	$ 162,000	$ 1,000,000
Number of Acquisitions | acquisition	1	2
Goodwill			$ 972,006,000	$ 971,951,000
Goodwill, Impairment Loss			$ 0	$ 0