Consolidated Statements of Changes in Stockholders' Equity (Parenthetical)	6 Months Ended
	Jun. 30, 2017 shares
Condensed Consolidated Statement of Changes in Stockholders’ Equity
Issuance of common stock for restricted share awards, shares	1,193,098
Issuance of common stock for the employee stock purchase plan, shares	40,378
Shares withheld for net settlements of share-based awards, shares	489,193
Purchase of common stock for treasury, shares	251,977